IROCZman15

iTrader: (25)

Those of you who have followed my build thread over the past two years, know that I have always planned on putting a single stage wet nitrous system onto the engine. Here is a link to the build thread in case you want to read it or find all the engine/powertrain/car information. http://www.njfboa.org/forums/showthread.php?t=69033 The goal for this car has always been a naturally aspirate mid-high 11's in the 1/4 mile , and then mid-high 10's on a single stage of nitrous. I am not a bracket racer, just simply a fella chasing a timeslip.

Anyways, the time has come for me to get this going. I am certainly no expert with nitrous, but I did run nitrous on the old 305 TPI engine for about 4 years. It made the 305 fun, but I basically just played around with it on the street, during autocross, and some drag racing. That kit was the NOS Powershot, which had 100 hp jets and 150 hp jets. Here is a link to the kit on Jegs: https://www.jegs.com/i/NOS/741/05151...QaAnd9EALw_wcB





So, I still have everything from this setup, and for my upcoming "version 1" of this upcoming nitrous system, I will be using most of the components. Instead of just drilling the engine with a 200 or 250 shot and having to buy new solenoids, I feel safer using the existing "smaller" solenoids for at least this fall 2021 season. I will be using the existing 10 pound bottle, its blow-down tube, the bottle pressure gauge and the main -4an fed line from the bottle. I also will be using my toggle switch setup that is mounted in the ashtray. I do not yet want a bottle heater, and I will never need a remote bottle opener since I can reach the bottle valve from my drivers seat. As mentioned, the NOS powershot solenoids are good for somewhere in the neighborhood of 150 hp (but I have read 175 can be done) so I will use those, along with the nitrous purge solenoid. I bought a NOS cheater wet-plate from a guy on thirdgen.org for $50 which was a heck of a deal. The wiring, and the relay will all be replaced with fresh new stuff, some colder spark plugs, and a new oxygen sensor with an O2 extender bung is also required. I am on the fence about using a fuel pressure safety switch, because I know it is a good idea, but mounting it in the tight area where I will have the fuel lines just might not work for me. I also do not plan to use a throttle mounted "window" activation switch, as I can control the nitrous both with my shifter mounted button AND also with the holley efi software.

I have been reading a lot about nitrous while using the holley sniper efi and I will get into some of that later. UNsure if I will be doing a progressive shot or not yet; maybe. This post is mostly for me to lay out the components and gameplan for everyone to look at, and then let me know their thoughts and technical opinions.


Bottle:
Use existing 10 pound NOS bottle with blow down tube.

Toggle switches:
Using the existing Nitrous Outlet ash-tray panel. I only plan to use the "master arming switch" and the "purge button". https://nitrousoutlet.com/i-30559860...tch-panel.html

Fuel Pressure safety switch:
undecided currently, but I will Probably get one
https://nitrousoutlet.com/i-30559952...-manifold.html

Oxygen sensor:
The nitrous guys that run the holley efi assure me that I will need a better O2 sensor as well as a special extender. (will add link later)


Lines/Plumbing:
I had used the braided -3an lines that came with the TPI kit on the TPI and they were good. They are way too long for my new setup. Instead of shortening them, I think i want to go with a hardline from the solenoids to the plate. Will do the -an flex lines to connect the fuel system to the solenoid, and to connect the nitrous bottle to the purge solenoid. But everything else I want to do with hardline.
- I am going to have to find a spot I am happy with to mount the solenoids in a spot that not only is visually appealing, but also serviceable and allows me to change jets easily. Therefore, instead of fighting with stainless steel lines at first, I might try to use some of my 3/16" (which is -3an) copper-nickel lines that remains from when I built my brake lines throughout the car. I have emailed Nitrous Express AND Nitrous Solutions who both told me that copper-nickle line is absolutely fine to use for hardline on a nitrous/fuel system. It will be much easier to bend, flare, and work with. However, they will not be shiny silver. If I can get the lines the way I want, maybe later I can re-create them with stainless. I will need to buy the proper fittings, tube nuts, and adapters. I also will need to buy a cheap-o 37degree flare tool, but I do have a tube bender already.
- Fuel line fittings will be needed too to T-off of the existing -8 fuel feed line. I will also re-install my Aeromotive fuel pressure gauge, and probably that fuel pressure safety switch, so it will be a cluttered area of fuel fittings and adapters.

Solenoid Locations/brackets:
This one is tricky, and right now I have about 3 possible options, but feel free to add in your suggestions. Number 1 priority is that the solenoids have to be mounted in a way that are visually appealing to me. I don't want to just have all sorts of brackets in random places with solenoids and lines hanging all over the top of the engine. No way. There are not too many choices that appeal to me, and maybe I could make my own later, but for now, I might use something like these and "drop-mount" them off the carb-mount studs. https://www.holley.com/products/nitr...parts/16523NOS Initially i wanted the solenoids all in that "valley" between the sniper and the thermostat housing. IT will get real tricky to make all the plumbing work that way, so I don't think its a realistic option. Also, the purge solenoid should be very close to the nitrous solenoid, so keep that in mind.

- Nitrous plate:
NOS cheater plate which i got for $50. It is capable of flowing up to a 250 hp wet shot, which is all I ever plan to put to this engine. link: https://www.jegs.com/i/NOS/741/12500...AaAkwmEALw_wcB I will buy some spare 4150 carb gaskets too for fresh gaskets during the install.

Jets:
The olde TPI kit came with two set of jets 042 + 053 jets for the 100 shot, and 055 + 070 for the 150 shot . I am unsure if these jets will work for the cheater plate, because I read this link which tells me different jetting :
https://www.429-460.com/t25799-new-n...-cheater-plate


Nitrous Solenoid Driver (not a Relay) and wiring:
The NOS TPI kit came with a 30a/50a 12v relay which I am sure still works, but the Holley EFI system seems to require a high-current nitrous solenoid driver instead of a relay? interesting.
https://www.holley.com/products/fuel.../parts/554-111


Spark Plugs:
I have only ever used the Autolite 3924 spark plugs on this engine, as these were the engine builders recommendation. The next step colder would be an Autolite 3923 plug, so I think I will go with these. https://www.summitracing.com/parts/atl-3923


Chris Meyer of EFI systemsPro has a great article on all of this too:
https://www.efisystempro.com/efi-pro...-nitrous-oxide










OR

Komet

Very cool thread, I look forward to your updates!

QwkTrip

iTrader: (22)

Seems like it's pretty much a standalone nitrous system. Holley Sniper EFI can't do controls and safety interlocks for you?

IROCZman15

iTrader: (25)

Do ya mean progressive ramping the stage in? Or enabling it and disabling it under certainly throttle positions and rpms? It so, yes it can, and that’s why I won’t need a micro switch on the throttle like the old school method. In that link I posted at the very end of my first post, Chris Meyer briefly goes through these basic features of the Holley software and shows some screenshots of the software on there too. Or did you mean something different that I am
overlooking?

LB9GTA

iTrader: (1)

Does the Sniper have a TPS?

I'd recommend using NGK plugs
I use -7 for street.
And -9 for 150 shots, although you may use -8
https://www.summitracing.com/parts/ngk-4554
Non projected plug

DIGGLER

iTrader: (1)

main items of concern that pop in my head....

1. you need dead nuts pressure monitoring for nitrous pressure
2. you need dead nuts pressure monitoring for fuel pressure, to be set while it is flowing through a jet
3. you can run carb fuel pressure or efi pressure, and you would change jet sizes depending on which you are using. much more info out there for jetting a cheater plate on carb pressure.
4. you can use standard relays to operate your solenoids, but if using a progressive you would use that instead.
5. you will need a bottle heating setup to get the bottle to 900psi and be able to keep it there.
6. you need a way to pull timing when you arm the nitrous or when the nitrous is actually spraying.
7. i would see about doing a standalone fuel cell with a pump inside. you can then set it up for carb pressure and take the load off of your in tank fuel pump running the engine. also, you can put higher octane fuel in there.
8. use crimped hoses only for nitrous, not the ones you make yourself. i had one blow apart in my face once.

IROCZman15

iTrader: (25)

Thanks guys. I appreciate the tech advice.

LB9GTA;
Yes, the sniper has a TPS sensor and a lot of the sniper tables are based off the TPS so it is always "in-play". For nitrous, there are software/programmable options to allow the nittous to come on (or turn off) at set TPS percentages. So if I were to pedal the car, and drop below the set percentage, the nitrous would turn off. You can add in a delay also, so if I got back on the throttle I could program in a small delay despite if I was at 100% wot or not. Is this what you were gettin at or ?
-Thanks for the plug suggestion, it might be something I change on over to after seeing what these Autolite 3923 plugs do. I picked the 3923 at the advice of the Engine builder who builds a lot of high horsepower small/big block chevys, many of them see nitrous often. he said for sure a 3923 would suit me right, but I am not opposed to trying those NGK plugs as well. thanks!


Diggler:
I have had ideas about doing a small fuel tank under the hood just for nitrous. While it would be cool, its not something I can afford right now, and every mod I do keeps making the car heavier and heavier...its surprisingly heavy. I also just really don't know if I like the look of the tanks under the hood. I still take this car to car shows and I try to keep the engine bay extremely simply, clutter-free and clean. having hoses and lines all over the place is very undesirable, so I would really have to plan out a tank and hose system that is discrete and clean.

1. as for the nitrous pressure, thats going to be a challenge for me going forward. I do want to do a bottle heater, but I would only leave the heater strapped on the bottle for racing events. They look ugly, and hte tank is very visible in the car. I do have a bottle pressure gauge on the bottle and i can read it from the drivers seat. I will have a purge solenoid setup, but since I only currently have one nitrous bottle, I will probably only get about 4 full passes with a nitrous bottle per race day. A secondary bottle would be great, but they are about $300 and I would have to put that on the "buy later" list

2. The fuel pressure of the system is currently regulated by the holley sniper with a regulator that is on the return port of the sniper. It is pre set to 58-60 psi and they are not adjustable. I have a racetronix 340 lph pump, with the upgraded heavier gauge wiring. I run a -8an feed line and a -6 return line to the in tank racetronix pump. I have an aeromotive in-line fuel pressure gauge on the fuel line, but I don't know how I would actually test the fuel pressure that is flowing through a fuel jet?? I spoke with racetronix about my setup last year and he said I should be capable of safely fueling the engine with an additional 200 shot and not starving anything for fuel. We did some quick math on this, but I don't have it written down.


3. see above....also I ran into the same info you mentioned about the jetting for a cheater plate using a carb psi vs fuel injector psi. I actually called Holley/NOS today on my lunch break about this exact question. My tpi system was at 43 psi fuel pressure and used a 070 nitrous jet with a 53 fuel jet (for a 150 shot). The tech guy on the phone said that now since I will have a 60 psi fuel system, I should still use the 070 nitrous jet but to lower the fuel jet to about an 040 and then watch my afr on datalogs. Since I will have more fuel pressure I should downsize the jet. He told me that LS style engines use around 60 psi, so I should try to search out a nitrous/fuel jetting for a LS because there is probably a jetting chart that would get me in the ballpark. he did say that an 070 and 040 combination would be close enough to start. Thoughts?
edit: found this onlinr jet calculator tool: http://www.robietherobot.com/nitrousjetcalculator.htm
and this chart for 55 psi efi plates: https://www.nitrousexpress.com/image...atejetting.pdf

4. While I wouldn't mind having a non-progressive setup, I feel that it is smarter to have the ability to make it progressive, therefore I went ahead an bought the solenoid driver so that I do have the option to ramp in a progressive stage. Seems to make sense long-term.

5. yup. I agree. see above. Would also like a spare bottle too.

6. the holley sniper software is capable of doing that. On my old TPI setup, I had used a MSD digital 6-Plus box to pull 4 deg timing on my 100 shot. The box worked great, but now I use the sniper and the hyperspark ignition. Both will absolutely pull timing when the nitrous is spraying. Spoke with my engine builder today also and he told me that he usually pulls 2 deg for a 100 shot (as opposed to what i used to do... 4 deg for a 100 shot). He said that I could pull 3 degrees for my 150 shot, or if I felt more comfortable, i could pull 4 deg for 150. He also said to target an AFR of 12.5:1 when the nitrous is flowing. Check datalogs and adjust accordingly...also the sniper can learn not only N/A but it can learn on nitrous and build its own nitrous learn table too.

7. yup, see above at the top

8. I do have some crimped hoses, they came with the tpi kit and are in the photo above. They are ridiculously long for the very short distance I plan to need. But, Maybe I will re-use those if I can't get the hardlines to work. I am aware of how to assemble ptfe lines, I did so for my entire fuel system from start to finish. So it is an option. I just still do not yet know how I am going to locate the solenoids and the cheater plate. Once I figure that out, I can start to get creative with the line routing. You had what type of line blow up? steel? yikes. not good. I do think my copper-nickle will work, even if just for a few months and I can redo the lines with braided ptfe or stainless over the winter. This first nitrous layout is probably "phase 1" and will result in some changes over the winter.




So,m last night I ordered most of what I will need. (I did not order any fittings, tube nuts, etc since I still do not yet know the solenoid layout) (also did not order more jets, as I gotta find a chart to see what ones I might need for a 100 shot, 150 shot, and a 175 shot)

- 4 solenoid drop-brackets NOS 16523NOS
- high pressure adjustable Fuel pressure safety switch -6an Nitrous Outlet 00-60001-6
- NTK oxygen sensor for holley sniper NTK554-100
- Innovate Motorsports oxygen sensor extender HBX-1 3729
- Holley High Current Nitrous Solenoid Driver 554-111
- 37 degree -an flaring tool SUM-900311
- 8 Autolite 3923 Copper spark plugs
- 3 carburetor gaskets

Stuff was ordered from Summit racing, and hopefully will arrive as expected on Friday, so I might make some progress this weekend. maybe


During my chat with Holley/NOS today, I asked for clarification about the Powershot solenoids that came in my TPI kit (which i will be reusing). I was told that my nitrous solenoid can flow up to a 175 shot and my fuel solenoid is capable of a 200 shot. This is enough for me for the rest of 2021, so I Just gotta find jets for these.

LB9GTA

iTrader: (1)

Please do not use the AF gauge for your tune!
Pull plugs, every time you make a pass, until you have a safe tune.
Fresh plugs, drive to the lanes and run it.
Stop after the race, pull over and pull the plugs. Check them.
Pull more timing than you need.
Easier to add timing later, than to not pull enough timing and blow your engine.
I'm talking from experience...

IROCZman15

iTrader: (25)

I wasn't clear about what I meant by that. I didn't plan on just making a tune and simply only datalogging to make adjustments. I would use the datalogged AFR to make sure my tune is not WAYY off.
- I know plug reading is super important. I did a bit of that when i was spraying the 100 shot on the TPI engine for a few years. I will have to re-train my self on what to look for regarding the plugs. I know that the "color change" mark on the grounding strap should be right near the bend of the strap. if it is too far either way, timing adjustment needs to be made. Also, the fuel ring on the porcelain. What else? I knew not to get iridium or platinum plugs too, thats why the copper Autolites were purchased.

-However, there is no chance that i can shut off the engine after I go through the traps and then coast all the way back to my pit spot. At island dragway you have to go around a tight 180 degree turn, over a birdge, around another turn, and to the timing tower to get your slip. The bumpy curvy road is only 8 feet wide, no room for hanging out and blocking other cars on the return road. The best option I have is to make the 1/4 mile pass, slow down in the shutdown, coast around the turns and over the bridge, to the timing tower, and then coast to my pit spot...where I would then turn off the engine and check the plugs. Basically this is what everyone seems to do, even the multi-stage nitrous guys are not getting towed back by atv's at this track. I have never once seen anyone checking plugs in the grassy area along the return road.. its just not how Island Dragway operates.

I FULLY AGREE with you about pulling more timing out and being safe about this, and then adding timing back later. I am not planning on going for the glory shot on my first outing. I will keep it safe, so probably pulling out 4 or 5 degrees for the 100 shot.

Some of the boxes arrive tomorrow, so I hope to make some progress on the install this weekend.

everyone, feel free to comment, question, or add info here. I very much appreciate all advice and criticism. I simply just want to make sure I do everything as best as possible.

NoEmissions84TA

iTrader: (1)

Check this out:

Orr89RocZ

iTrader: (20)

These guys have more nitrous experience than me but on my 383 i ran several bottles thru it at 150 shot levels and i basically used track mph and air fuel for tuning. Stock recommended jetting in my hitman kit was way rich. I jetted the fuel down a lot and picked up 4 mph. I think i targeted 11.8-12.0 afr. I pulled 3-4 deg i think. I think i had 7 heat range ngk plugs but i did have air fuel distribution issues as i found one plug did end up eating a ground strap lol. But it ran hard. Nitrous is fun but adds up lol go thru gas quickly i found

DIGGLER

iTrader: (1)

i ran a 1 gallon cell sitting in the battery tray location for my standalone. i had a walbro 180 or something like that in there and it had no issues delivering what i needed. ran pump in tank and race gas in cell for awhile.
One of the best reasons for running carb pressure on that cheater plate is there is a huge amount of r&d on it available on the net. if you look at the jetting chart that came with that plate, it is actually way rich. in fact, you could pretty much swap the fuel and nitrous jet recommendations and it would come out about right. so to save yourself several dozen spark plugs and bottles of nitrous trying to get it dialed in, you can simply put it to where some of the guys on yellowbullet.com recommend. (fuel pressure and jet sizes) there was tons of info on that site at one time.

for timing, i was always extra extra safe. i think i was pulling 6 deg. on a 150-175 shot. base timing was 32 for my combo.
you will want to read plugs, but i would recommend to save some time and money go ahead and find your 2 leanest/hottest holes and just check those after a pass. that way you wont have to change out all 8 plugs every time you want to get a read on the tune.
stainless braided line blew up in my face. i was a complete moron and didnt even realize there was a different hose type needed for that amount of pressure, so i made my own. it worked for awhile but eventually came apart at the fitting. there wont be that much pressure after the solenoid, so you could possibly get away with making those. hard lines should be fine.

DynoDave43

iTrader: (11)

I'll be following this for sure. I know next to nothing about nitrous, but I am trying to learn. I do have a few questions if you don't mind...

The new oxygen sensor....why? Was the sensor that came with the Sniper system not a wide band?

Oxygen sensor extender. This moves the sensor further out of the hole / pipe to keep it cooler? Do that also not make it less accurate, or slower to respond, not being fully in the exhaust stream?

Copper plugs. You said you knew better than to run iridium or platinum. But I don't! Why are they a no-no?

IROCZman15

iTrader: (25)

No Emissions: wow, that is incredible! I am definitely going to try that out. Super cool

Orr : I was hoping that you would see this thread and chime in! I remembered that before your turbo 555 monster you had a nitroused 383, so I am glad you found my thread. Good to know that the 150 shot is going to be strong enough for me to feel the power, yet small enough where I can focus on reading plugs, afr, datalogging and keep the engine safe and happy. I think the 12.0 afr is a good spot for me to start at. I still have to figure out a proper array of jets to buy to give me enough adjustable options, but without spending huge money on an entire suit-case of nitrous jets! Also, See my write-up below for what I plan to do regarding bottles and fillups.


Diggler. I do agree. That cheater plate was on artic-whites carburetor engine and I know that the cheater plate was designed for the carb setup and not an efi tbi setup with higher pressure. While it would be way cool to have a stand alone fuel cell and pump under the hood, for this current season/setup I am not able to afford it and not able to swallow the concept of adding more weight and clunky stuff under the hood. The cleanest system I have seen is the stand alone Fitech fuel tank/pump, and it is still too expensive and does not fit the design/look of my engine bay layout. I think I am stuck jetting the cheater plate off of the 60 psi range of my current fuel system.
- that is a great idea about figuring out which two cylinders run the leanest out of all 8! Typically when i checked plugs I would check the ones that were the easiest/quickest for me to check (like 1, 3, 2 and 8. But I see the logic in your statement, and i can spend some time figuring out what cylinders are the leanest of them all and then use those as a bottom-line to tune upwards from. Awesome! Base timing for this engine we have found that 34.5 degrees at full advance. So if I start out with a 50 shot, ill pull 2 deg. Read plugs, and then go from there on upwards...safely. I will probably post photos on here for group discussion.
-ah gotcha, a briaded line blew up. Now I understand. yes there are different versions of braided hoses. from my experience the PTFE braided are best (currently). Today I was chatting with a friend who used to work on slammed trucks, imports, and low riders. he used to bend up all sorts of stainless lines for those cars and showed me some photos of the tricked out plumbing he had done. He said he would be glad to help out and has some high dollar flare and bending tools. We discussed that it might be smart for me to put in the effort and build my "version 1" set of lines out of the copper-nickle with all the fittings I need and get the system up and running. Then, when he has time to come over, we can take my copper-nickle lines off, and duplicate them out of stainless steel (and adjust the bends as needed) and then install them after a good polishing. That seems like a good idea. Thoughts?

Dynodave, glad to have ya here too, feel free to ask away and hopefully these experienced guys can answer also. As for your current questions, your timing about the oxygen sensor is perfect. I wrote up a description in the "sidenote" just below this one. Long story short, the current oxygen sensor (and the new extender) will be just fine. No need for the (expensive) NTK sensor, that is for other Holley EFI systems, not my sniper setup. As for the extender, everyone on the holley forums is very vocal that the HBX-1 extender is a must have. Somehow, scientifically, it does not skew the readings and the sensor performs exactly as it should. Otherwise I couldn't see it being recommended by so many people for so many years. It is super import and for any type of forced induction. It also helps with cars that produce a lot of water in teh exhaust and it prevents the o2 sensor from being thermally shocked by water droplets. There is some really good tech info here in the post by Danny Cabral at 5:08pm on 1/20/13. https://forums.holley.com/showthread...4322#post14322
-regarding the platinum/iridium plugs, I think most nitrous companies say to use copper. Platinum plugs tend to retain heat longer and therefore the stored heat is more likely to cause pre-ignition/detonation. Also, Platinum tipped ones can occasionally have the tips falloff and then your plug gap is different/bigger. Also, the cost per-plug is much higher and if I am going to be cutting open lots of spark plugs while dialing in the jetting, the copper plugs are more wallet friendly. I am sure some of the other nitrous guys on here could also clarify more on this topic too..



Stopped by Bruce's speed shop today to get my 10 pound bottle filled. I had emptied it down to zero so it was dead empty. Bruce now charges for nitrous by the pound, which is good, because I will just need to get the bottle topped off from time-to-time and not need a full fill. I am considering a second bottle to keep as a spare full bottle, as this will cut my trips to his shop in half. new bottles are expensive thought at $300 a piece! yikes


UPS brought my summit racing order today.
-sidenote: I will be returning the $290 NTK wideband oxygen sensor. I had done a bunch of research on the Holley EFi websites and the NTK sensor is highly recommended for nitrous(forced induction) setups. Yet, just today I spoke with one of the top tech guys via email who told me that the NTK sensor is compatible with all other holley EFI systems, however it is NOT compatible with the holley sniper system. So, I verified, that my best course of action is to use the Innovate HBX-1 extender along with my current oem holley bosch sensor. It will be good to go. So, I might take the money from the returned sensor and either buy a second nitrous bottle, OR buy a removable bottle heater. Those bottle mounts with the bottle heater built in are cool too, but way too expensive for me. There seems to be a lot of bottle heater options, so I will have to do some research on that topic.














Hope to make some progress this weekend with mounting and wiring, that way i can figure out what fittings I need to order. Also, still waiting on the fuel pressure safety switch to arrive, delivery scheduled for next Thursday.

IROCZman15

iTrader: (25)

Installed the HBX-1 Oxygen sensor extender today. Made sure to line up the indicator dot with the incoming stream of airflow from the engine.




Painted the side surfaces of the cheater plate with an aluminum colored spray paint and high temp clear. Sanded down the mounting surfaces to be smooth too. new gaskets on each side.








Spent some time trying to figure out the best functional/aesthetic/logical places to mount the 3 solenoids. (Fuel, nitrous, and nitrous purge solenoids). Gotta make sure that the in/out ports will be in the right direction, as well as trying to keep the purge solenoid close enough to the nitrous flow solenoid.











Ignore the placement of the blue t-fittings in this, it was not int eh correct spot but I was checking stuff clearance related.




I am going to have to come up with a list of proper fittings and adapters to order, but I think i might have to wait for the fuel safety switch to arrive. maybe. Unsure if I will do all black fittings or blue nitrous fittings and red fuel fittings.

articwhiteZ

iTrader: (56)

IF your want to pick up a 1 gal fuel tank and reg for the NOS set up. I have it all new in boxes..will make ya a deal. to save ya money. and make room for me at the same time..will get some picks up in a few.. top name brand parts..

IROCZman15

iTrader: (25)

Articwhite: possibly, but not for this short remaining 3-month time period I have left before winter-time. I just want this system up and running so that as soon as the car is ready, i can get to the dragstrip and HOPEFULLY get a 10 second timeslip. During the fall, if I find that I would benefit from a fuel cell system, I might take you up on that. But I gotta keep my budget in mind and pick and choose my entire exhaust system renovation.


Got most of the engine bay wiring done today. Wired up the nitrous driver solenoid, the power and ground wires to the nitrous/fuel solenoids, and the purge solenoid too. Gotta finish covering everything in protective split-loom, and then run some wires into the cabin to my buttons.

Gotta place the order for the -an fittings too, maybe later tonight. Gotta also change the spark plugs and then start to get into the holley software to build a base tune. Oh, and also, I gotta order some nitrous jets. have yet to do the math on what jets I'll need for a 100, 150, and 175 shot, with a fuel pressure at 60psi.

BadSS

You’ve been given good advice, but I’m adding a couple comments for insurance/safety.

Fuel pressure switch – A must, which you said you have, to kill the nitrous if your fuel pressure drops, preventing catastrophic failure.

Window switch – set above the two-step (or your launch rpm) and below the rpm limiter if one. Prevents another catastrophic failure if you hit the nitrous too soon when the two-step is still “active” and cuts it off before getting into the rev limiter.

Internal/Interior nitrous pressure gauge – As already indicated - need to make sure the pressure isn’t too high or low before making a pass – I prefer one with a low/high warning light. I’ll add that if you put the bottle in the spare tire well of a 3rd Gen, the exhaust can heat that area up when there’s no airflow (like on a dyno or long idle periods). Pressure can creep up and exceed the safety mark – will need to be able to see it and bleed off pressure with the purge solenoid. I also prefer running an interior fuel pressure gauge with a built-in warning light set a few pounds under the safety switch cut off pressure – gives a heads up if there’s about to be a problem.

Big in-line nitrous filter – Two approaches here. 1) You can connect it to your bottle when you get it filled to make double sure any trash that may come from the fill bottle is filtered – even if the place has one, you will know you have a clean bottle. 2) If you don’t want the shop to perceive you bringing your own filter as an insult to them, or you think you might need to borrow a bottle at the track, you can put it in-line near the bottle and for easy access. If picking just one, I prefer the later, just in case there happens to be a need to “borrow” a bottle – which I’ve had to do a couple times in my earlier years when I only had one spare - lol.

Timing Retard - I know you’re working on the nitrous retard, but having it kick in with the activation of the solenoid is key.

Nitrous Lines - I never had an issue in over 30-years of building my own (and other’s) nitrous lines (proper PTFE hose). Where you get into trouble here is using different manufactures fittings and lines. Not all PTFE lines have the same size inner thickness of tubing or opening – the olive that sits on the outside of the inner lining and the nipple on the fitting have to be compatible. If you’re having a lot of trouble getting on either the olive or the fitting, then you more than likely have a miss-match.

Example of different manufacturer’s 4AN PTFE hose. IMAGE

General comments
se a true nitrous AN fitting with the filtered screen on the inlet of the nitrous solenoid. If you can’t tell I’m a freak when it comes to making sure no trash finds its way to the spray bar.

When setting up someone else’s carbed nitrous system I always use a small fuel filter at the gas solenoid inlet for the same reasons as above. If you have a good high quality fuel filter already in-line before the “T” and you’re comfortable with the filtering of your fuel system this would be overkill.

I’m fairly certain that not all the NOS plates are the same (could be just the fittings I suppose). However, if I were you, I would check Holley's website to see what if any difference they list for the jetting for a particular HP rating on the PowerShot, Super PowerShot, or Cheater Plate - obviously you would need to know which one you have. Anyway, check the nitrous and gas jet recommendations for the appropriate plate, then use some math to figure out which gas jet you would need for the EFI fuel pressure. When in doubt, go fat at first and begin leaning out by reading the plugs (as other said).

You may want to consider putting the solenoids at the rear of the engine, especially the nitrous solenoid to make it easier to route the purge tubing. As you said, putting everything up front will be tricky and to me seeing a bunch of lines running everywhere isn’t going to be appealing. To me it’s better to not see it or lessen the visibility.

Certainty not an all-inclusive list, but there are a few extra things for you to consider.

HTH

IROCZman15

iTrader: (25)

BadSS: awesome reply. thank you ! some clarifications and my explanations are listed below
- fuel pressure switch. still on the fence about this one. see my narrative below. Also, I didn't have one with my previous nitrous system on the tpi 305 which I ran nitrous on the street pretty often for a good 6 years, and that was using the stock pump. I know, I know, different pump now, different engine, different lines, different demand. etc. But the Holley sniper can sense a lean condition and instantly kill the nitrous too as a fail-safe.


window switch- Luckily this is a feature involved in the Holley sniper software, and I can set it to whatever rpms I choose with just a couple mouse clicks. I am thinking of only allowing it to spray between 3,500-6,000 rpms. thoughts??

- nitrous pressure gauge. so I currently have a nitrous gauge mounted to the snout of the actual bottle. the bottle is on a NOS bottle mount which positions the bottle in between the rear seats just on top of the driveshaft tunnel. I like it there, as I can turn the bottle on and off from the drivers' sear. It is not in the trunk well, but that is interesting you mentioned about the exhaust heat back there, I had never considered that. I like my bottle where it is on the driveshaft hump, so it is staying there. I can not read the gauge when I am belted into the seat, but I can read the gauge as I get in the car before getting strapped in. If it is high, I can purge it down accordingly before getting strapped in. In the future, It might be something I add a secondary nitrous gauge (and fuel pressure gauge) into an A-pillar gauge cluster, but I definitely do not want to have an excessive amount of gauges in my cabin. Aesthetically, i won't do something like haphazardly mount gauges all over, so i have to figure out a way to make it look good. This would be a winter-time project for me, but it does seem like a great idea if I can find a clean way of doing it.

filter- I had seen those big in-line filters while shopping for my nitrous fittings just a few nights ago. I might add one, but I don't want it to be visible. Its a bit unsightly and this still has to be a street, show, strip, autocross car..not a race car. I have run the small in-line nitrous filters in the past, and i ordered a fresh one (which will arrive tomorrow), but it is not the big kind you suggested.

timing retard- this will all be the responsibility of the holley sniper ecu to do the timing control. However, it is my responsibility to program the timing into the sniper software/tune. In the coming days, i will definitely be posting some screenshots of the holley nitrous tune that I plan to do for my initial testing. Hopefully you (and everyone else) can analyze them and see if I have anything incorrect or in need of adjustment.

lines: yea, I have built a bunch of PTFE lines before. My whole fuel system i did that way. Kept it all one brand too.. like ou mentioned, some companies have different measurements. I ordered ALL of my fuel/nitrous fittings from summit but they are all Earls (holley) and NOS (holley) fittings, so they should play nice together. As for using braided lines; the only braided lines on this whole setup will be the -4 nitrous supply line from the bottle-firewall and to the engine. The rest of the nitrous system wil be 3/16" hard-line that I will bend out of copper nickle, tube nuts, and tube sleeves. The only braided flexible fuel line will be from the fuel tank-body to the engine. The rest will also be the 3/16" hard-line. hard-line will look cleaner, if i can do it neatly.

general - yes, that small -an nitrous filter you mention, thats the one I have. I was going to put it right before the purge solenoid, but now that I think of it, might make more sense to put it in front of the nitrous flow solenoid? I have a pretty stout fuel filter in my system (the magnetic racetronix) one, and I am pretty comfortable that it does its job well. I swapped out the filter element after about 3 years of use (9,000 miles) and it was super clean. I installed a new one anyways, but since the "old" was so clean, I put it in a box and into my spare parts cabinet. Also, yup, see my typing below for the jet info. They arrive tomorrow. I initially wanted the solenoids at the back of the engine bay, but there is definitely no room. It would make future engine work a lot more of a headache. I contemplated my options for a long time, and for my first "version" of nitrous on this engine, I am going to keep them where they are. Maybe one day a new location will be more suitable or possible, and I am willing to experiment, but at this point in time, I kinda want to get this car back up and running asap.








My update

fittings ordered and will arrive tomorrow. There is a lot of them and I am not thrilled about having that may connections to make on the fuel and nitrous systems, but I will take my time and do it as neat/properly as possible. It is a lot though... but that is because I am using 3/16" hard-line. if I was just using the -an braided hoses, there would be less fittings, but then I would have swoopy "messy" lines all curling about in a very confined area. Not desirable for me.

Also ordered some jets after doing some calculations to figure out what will work for a 75 shot, 100, 125, 150 shot. Some of the jets I already have will work too, so I only had to order about 6 jets for now.

Was going to install the Autolite 3923 spark plugs, but I was hesitant to do so after checking the gap on them when I took them out of the box. They appear to be factory gapped at about .038 to .040 and I think that is too big of a gap. probably ok for N/A, but for a small nitrous shot, I would think I should go .030 or so. Thoughts?


Took care of about 95% of the wiring too. Well, actually 100% if I do decide NOT to use the fuel pressure safety switch. If I do decide to use it, I will have to decide if I should wire it in with the (master-arming switch -> ecu) or (momentary switch on the shifter -> ecu) Not sure if it matters, and still not even sure I want to install it. Some of the EFI and nitrous gurus I've talked to elsewhere say that the switch isn't necessary, and other people seem to like having multiple safety features in place. Again, keep in mind, the sniper ecu will instantly kill the nitrous if it reaches my lean-cutoff parameters.

In wiring the nitrous to the ecu, I had to loose my 2-step rev limiter because that occupied my input#2 spot of the 10 pin sniper connector. I'm ok with not having a 2-step as I am just foot brake launching at 1,800 rpms anyway.

IROCZman15

iTrader: (25)

Fittings arrived very late in the day yesterday, so I didn't get to install anything until after work today. Again, its a LOT of fittings, but that is because every hard-line connection needs a tube-nut and tube-sleeve...also every connection at the solenoids needs a NPT-to-3an adapter. I also bought some extras just in case one or two get boogered up accidentally. Started mocking things up on the nitrous side today, and most of it is in place, and some of it is tightened down. Tomorrow I hope to make some progress on the fuel side of things. Had some ideas of where I wanted the purge line to purge, and I think I might get creative and use some of my old fittings to make a dual-purge setup that comes out from the cowl area. the fittings and lines would be hidden below where the windshield wipers rest with that mesh screening covering the open void. I am short a single -4male to -3 male fitting, and summit/jegs/holley are out of stock for this fitting, so I am hoping I can get it over at Bruce's speed shop instead. if not, I will just do a single purge pipe for now, and then add in a T-fitting (with the -4 to -3 adapter) later. I know, a LOT of fittings and a lot of connections for possible leaks. Maybe this will all get changed later in the future, so this is version1. Any comments or advice, feel free to let me know.























Jets I now have: .021, .024, .029, .032, .042, .050, .055, .062

The combinations I came up with for my 60 psi fuel pressure setup is:
75 shot = .042 nitrous + .021 fuel
100 shot = .050 nitrous + .024 fuel
125 shot = .055 nitrous + .029 fuel
150 shot = .062 nitrous + .032 fuel



I still am curious about the spark plug gap too, any thoughts (see post above this)





Worked up a quick tune file for a small 75 wet-progressive test shot. Set up some safety parameters or failsafes too. Keep in mind, that I will be letting off the button and not spraying nitrous during the gear-shifts. Therefore the computer will see this as "pedaling" and I have to account for that as I put in some of the values in tune (screenshots below)

DynoDave43

iTrader: (11)

Looks like a very clean install!

IROCZman15

iTrader: (25)

well this is exciting for me at least, not sure if anyone else is enjoying! Sorry for all my excessive typing and posting, just showing my progress and in case anyone has any tech advice, I would rather they see what I am putting on the forum, and send over any advice as I progress.


Got the fuel side plumbed up today. A couple complicated bends. Turned out pretty good, but I will eventually make some neater lines for version2. Decided to do a dual purge since I had hard-line and fittings. I only needed one additional specific fitting, so a quick ride over to Bruce's speed shop in Rockaway, and bought it. Buttoned everything up and pressure tested the nitrous side by turning on the bottle. No leaks at all at any of the fittings, and the dual purge worked as intended, had my wife test it. Primed the fuel system and it shot to 60 psi on my in-line gauge, then dropped down to about 45 after 5 seconds, and then slowly dropped to 22 psi where it held for about an hour, until I primed it again and it still held. No leaks at any of the fittings either.

Peeled off the protective blue tape, zip tied a few things up, put all the spark plug wires on and checked fluids. Loaded up that "baby" progressive 75 shot tune (see above). Engine ran fine as normal, even with the new colder plugs it acted the same. After warm up I only had time for a quick test drive just to make sure all the systems (lines, fittings, electronics, tune, etc) functioned properly. Did a brief test rip and it took it just fine. I know a slow progressive ramped 75 shot is hardly anything, but it was nice to feel it come in, and to smell that smell of burnt nitrous in the exhaust fumes. Will examine the datalogs soon, as well as pull out some plugs and see how they look too.

I do have some cleanup to do under the hood still, so this isn't the final result, but it is a working system. Also, would like to polish the valve covers, sniper unit, and whatnot. Car show season and some Test -n-tune nights are coming up soon.

LB9GTA

iTrader: (1)

Nice job on the hard lines.

I agree on the 1st nitrous hit. I get giddy.
My smallest shot is 150, and it's a rush.

DynoDave43

iTrader: (11)

Congrats on a successful first (nitrous) drive.

QwkTrip

iTrader: (22)

Cool. Beast mode is coming soon!

DIGGLER

iTrader: (1)

letting off the button on shifts might get awkward, i would be interested to hear feedback on that. mainly on the bigger jets where the car will really fall on its face when you get off the button.
just tossing it out there, but if you dont drive the car long distances often, you could swap to a th400, tight converter, and something like a 3.42 gear. the car would still be driveable around town and such, and faster at the track with a big gain in reliability.

BadSS

Esthetically speaking it looks good – functionally, going to point out areas of potential concern.

DISCLAIMER – CONTACT YOUR NITROUS BRAND TECH LINE TO CONFIRM. Most of my experience is with carbed applications back in the 80s and 90s. I’ve installed and run a lot of kits from entry level kits to foggers and never had an issue, but I have been out of the game for a while and only run a couple smaller EFI kits.

General Info/Rules Regarding Solenoid to Plate:
The line from the fuel solenoid should not be longer than the line from the nitrous solenoid. If possible, I run about 1/2 (carb) to 1/3 (EFI) the length of the nitrous line. This helps insure against an initial lean hit/spike. Realistically you’re only looking at hundredths of a second considering most line lengths and I know many run equal length lines without issues. A lot will depend on the fuel delivery supply and the piston alloy whether or not it could actually hurt something.

The shorter the nitrous line (still needs to be longer than the fuel to solenoid line), the harder the initial hit of nitrous – the longer lines will give a softer initial hit. This is a useful tuning method for non-progressive kits.

I believe a 2ft long 3AN line will only support about 175HP. If you’ll note, the small kits sold may have the 3/16” hard line from the solenoid to the plate, but the larger kits will have a 4AN line with a 4AN fitting for the solenoid side and a 3AN fitting for the plate. A single 2ft long 4AN line can provide around 400HP (more than most single solenoids can flow).

Specific Comments:
So, with how you've run the 3/16” hard lines to the solenoid, consider about 175 as your cap regardless of the solenoid size. If you want to run any more than that, you’re going to need to replace that hardline to the solenoid with a 4AN line. As short as the hard line is to the plate, 200 might be possible, but consider running a 4AN line with a 3AN fitting to the plate if you want to run more. A 175 shot may be about tops for you anyway – dependent on the piston composition and ring gap.

Not as critical on the smaller kits, more so with the larger kits; you want to make sure you have plenty of fuel available going to the fuel solenoid. You’re probably fine with what you have now for around the 150 mark, but much larger, I really think you’re going to need more fuel volume at the solenoid than the 3/16” hard line can deliver. When you pill up, go in small increments and really watch the A/F ratio when spraying. Also, if you see a significant lean spike at activation, you’ll need to reconfigure the solenoid layout to shorten the solenoid to plate fuel line - or at least put a timed delay on the nitrous solenoid.

Letting off the button for shifts can be a pain, but it is what it is if the transmission won’t take it. I had to let off on shifts before installing the TH400 – ever since then, no problem holding the trigger between shifts even with a 350 shot on top a 600HP engine. As Diggler said, the TH400 is a big bump up in reliability and consistency, but may not be an option. I have set up a window switch to kill the nitrous before the shifts for a couple people, but I personally prefer to do it manually. Plus typically you’ll run a little better time shifting at different RPMs going into 2nd and 3rd and will have to compromise a little using a window switch. That said, the majority of time for most street cars you’ll run as good or better times on the button short shifting – so try that and see what happens for you.

Anyway, just some things to consider if you see you’re having issues. Good luck and have fun with the nitrous, it’s a rush but can be addictive!

IROCZman15

iTrader: (25)

thanks fellas. Any and all advice is much appreciated.

Diggler: yea, some people have mentioned that a different geared transmission would be beneficial for drag performance. However, I still do actively autocross races, car shows that are hours and hours away, and I street drive the car a ton too, rain or shine. So the 700R was the sensible choice, and I have the converter setup on a manual-lockup based toggle switch (my old oem fog-light dashboard button). I'm going to be keeping the 700R for as long as it can hang in there with this power level. But I am certainly open to ideas on future options. I did have this trans built by Dana's ProBuilt Automatics and I went for the top of the top option; everything is as best built as it can be.


BadSS: I especially appreciate you going into detail and explaining all of that. I see what you are saying about the length of the nitrous line compared to the fuel line. That is a concept I had no idea about when I was mocking-up the components. Hmm, I am going to have to certainly keep an eye on if it becomes an issue with a hard lean hit, especially on a "fixed" shot compared to a non-progressive shot. And yes, I know I limited my setup by using the 3/16" hardline and -3 fittings. I think I am going to be ok with that, at least for a few years time. The engine (which I probably should have posted the engine build sheet) was more setup for "hardcore street use" instead of full on drag use. I told them I am going to be running nitrous, for sure, so they made sure to account for that with ring gap. Since my fuel pump/system, and other car systems are still of the street mentality, I never really planned on going bigger than a 200 shot, ever. Not in this car at least. So with the limit of my solenoids, my 3/16" hard lines, fuel system, heavy car, tight 3,400 converter, and ring-gaps, I think the 175-200 shot will be the absolute most I would ever go with. Already, with the 75 and 100 shot street tests, the car feels plenty fast for me for now. I do know that my ridiculous restrictive 3" exhaust has got to go away, and that will happen this winter-time. If a better exhaust and a 175 shot gets me some time-slips I am happy about, I am going to say "goals achieved" and scale back the heavy upgrades on the car, and simply just enjoy it and race it while saving money for another project. the car has been with me for 21 years now and its so damn close to where I wanted it to be when I was just 15 years old as a kid... and the car won't ever be getting sold or sent away. It has just been a heavy past few years of heavy upgrades recently, so running mid-high 10's on a street car that I drive to the track, take to car shows, autocross, and enjoy... that would be the :goal achieved" I am looking for. If it was a pure drag car, lightweight and trailered, that would be a different story.



My update:

thanks fellas. Took the car out for a few quick test runs locally. A progressive 75 shot, a fixed 75 shot, and then two brief fixed 100 shots. It pulls hard, I love it. I took some datalogs, and I am still trying to learn how to understand a nitrous datalog. Mostly to make sure my AFR is safe and the engine is happy. I also pulled plugs after the 75 shots and those looked good to me. I Probably should either buy one of those magnifying glasses with a light on it, or start using the hole-saw method to cut the plugs apart and see the fire ring on the porcelain. Timing marks on the ground strap are right at the bend of the strap, and my timing is fixed at 32 deg when the nitrous is on. Normally is it is at 34.5 deg at wot, and on the log, the bright yellow "flatter line (upper graph) is my actual timing. The darker-yellow colored "box shaped" line (lower graph) is when i am actually spraying the nitrous, the light blue "box shaped" line (upper graph) is telling me that my "timing modifier" feature is active, and I have it to hold the fixed 32 deg timing for .5 seconds AFTER I am off of the button.

Also, I am currently NOT spraying during the shifts, but on track day I probably will keep the button down during the shifts. The AFR trace seems to have lot of spikes when i am on the nitrous, so I have to find out if that is "normal during nitrous" or not. I thought there was a way I could smooth the data-points, but I can not seem to figure out how. I'm sure I will get all this sorted out soon enough, but in case anyone had any input on reading a nitrous datalog, feel free to let me know your technical thoughts. Thanks

I do think I will end up using the $ that I got from returning the expensive oxygen sensor towards a bottle heater. As discussed above, it would certainly help me maintain a more consistent bottle pressure and I would also need less trips to Bruce's to get the nitrous bottle filled.






.


engine build sheet:
(what would you say a proper ring-gap would be for the 175-200 wet shot.. is it about the .020 gap that is on this build sheet?) to me that .020 does seem a little tight, so maybe 150-175 shot is my limit?

BadSS

Well, they added more than enough piston to wall clearance for those 4032 alloy pistons to handle a 150 shot. However, the .020/.020 ring gap is a little tight – at least it’s a little tighter than I typically would set them for a 175 shot. It’s a bit of a crap shoot for a builder when setting rings for folks running nitrous.

Even though it’s better for a builder to go a little larger on the ring gap than you REALLY need, if the car is used more for the street than strip, especially if nitrous will see very limited use, I’ll typically go a little tighter than the typically recommended nitrous gap percentage (they vary depending on the manufacturer though). Again, that’s a little risky for a builder - especially when people will say they’re only going to run a 150 shot and end up running a 350 shot. However, based on my person experiences and the number of engines I’ve built running nitrous without issue you can get away with running a little tighter ring gap than recommended. That said, if I wasn’t going to run more than 175 shot, I would have set your rings to .022/.023-inch.

If you’re careful and make double sure your mixture is good you may be OK to run a 175 shot without issue – I personally would not run any more than that. However, I’ve always used more forgiving 2618 pistons and never built an engine with 4032 pistons when someone was going to run nitrous. SO --- CHECK WITH YOUR NITROUS KIT’S TECHLINE (in fact call a couple) to see what they say and then decide for yourself.

NoEmissions84TA

iTrader: (1)

Straight from Mahle: https://www.google.com/url?sa=t&rct=...njuek6Vq1dg9rW

DIGGLER

iTrader: (1)

yea ring gap is a bit snug at .020. stay with the smaller pills. i actually had mine set up in the .025-.026 range just to be super safe.
bottle heater is mandatory. for your jetting chart to work out correctly, bottle pressure needs to be 900 on the dot. if its lower than that you will be rich and performance will fall off. in fall and winter you will find the pressure will hang out way low, like 600 or whatever. in the summer sitting in the sun it might zing up to 1200+. too high for the solenoids to operate, in fact.

IROCZman15

iTrader: (25)

I know I say this every time I reply, but THANK YOU fellas. learning the proper tech from the right people is the best way for me to learn.

On one hand, I am kinda glad to know what my nitrous systems limits actually are, and to learn that they coincide with my current powershot solenoids, and probably the limits of my fuel pump. This means I won't have to budget $ for any bigger solenoids, lines, hoses, or fuel pump. That makes my wallet happy. And, since this car is much more of a fun street car, compared to a purpose built drag car, that 150-175 shot limit is totally fine with me. Awesome. Some brief street tests on the 100 shot and this car does feel like it should click into the high 10s, even with my ultra restrictive exhaust.

My Nitrous Outlet X-Series bottle heater arrives tomorrow from Summit Racing. I plan to hopefully get it installed and tested on Friday. I have a car show to go to this Saturday, but I am hoping that next weekend I can go to a Test n Tune event at the track. I've spent a lot of time the last few days researching how impreitave bottle pressure and nitrous system pressure truly is. As mentioned above, the bottle heater is a must if I want to have any chance of keeping the engine happy, healthy, and consistent.


Question:
- What would be a safe/normal rpm to start spraying nitrous at?
I've heard the old rule of thumb that you should only spray at WOT, and I set my parameters to only allow the solenoids to flow when my TPS is above 85% no matter what the rpms are at..... but.... how low in the rpm band is too low to spray. The reason I ask, is I am curious if I should start PROGRESSIVELY spraying at the hit. With my setup (street car) I only have a foot brake, no trans brake etc, and I can only hold about 1,800-2,000 rpms on the line before the car starts to creep. The converter is a 9.5" Edge Racing converter with a 3,400 rpm stall and lockup. I wish I could launch harder/better; my best 60foot is a 1.62 .. and that is barely lifting a front tire mayyybe 1milimiter off the ground.
My thought was to load in the jets for a 100 shot, but have a progressive ramp from 50% (so 50hp) at the hit and then about .8 seconds in, I would have it ramped to 100% of 100 hp. If the car can hold/hook/launch, it should put my front wheels up in the air and hopefully a mid 1.4x sixty foot? It will zip through 1st gear real quick with the transmissions 3.06 first gear ratio and my 3.91 rear gears, but is it a good idea to spray instantly as I launch, either progressively or even a fixed 100 shot?

Badas.sbird

If you look at your log with the unstable AFR with nitrous, are you sure that isn't the progressive ramp before it goes 100% DC on the solenoids? You can see that it evens up eventually. The start or on point for nitrous sometimes depends upon the converter but it is never a great idea to start any lower than 3000 rpm. This will ease the hit of the nitrous on parts. The application of nitrous at low rpms, especially in a small block, will create extreme cylinder pressure. The 3000 rpm start will mitigate this and you generally don't need this because with some converters it creates a natural delay to allow the suspension to react before the hit.

DIGGLER

iTrader: (1)

i would bring the nitrous on at 3k and off just before the limiter. 100 shot with progressive off the hit would probably be good, although i think i would shorten the ramp to something like .3-.4 or so.
if your drivetrain can hold up and not spin, you can give it the beans right off the line basically. i had a launch rpm limit at 3k on the transbrake, and nitrous came on as soon as i let go of the button. works good until traction/chassis limitations show up.

IROCZman15

iTrader: (25)

Great info, thanks. So, I actually myself had initially thought that 3,500 was a good number to start the nitrous on when I made my first two test hits just last Friday. Then, I dropped that to 3,000, for a test hit the next day, and on the most recent test day, I dropped it to 2,600. However, on that hit, i was going from a roll and I did not actually press the button until much much higher in the rpm band of first gear. I like that 3,000 rpm number you have mentioned. I think that will help me knock down an awesome 60 foot time and perhaps even leave with a wheel in the air for a nice wheelie photo opportunity. Like you guys have mentioned, this will be where traction/suspension issues might begin to show up, so I will do progressive shots first. I also like the idea of a shorter progressive ramp too. On my first two test hits last week, I had a 2 second progressive ramp, and I quickly learned that it was wayy too long of a ramp for such a small shot. However, that was the safe way for me to do it on my first test hits, because it would have given me a moment to get off the pedal if I heard or felt any issues. So, even though I am still testing on the street (and next weekend at the track) I will start to give it a little more, since I now know that the system itself is doing what it is supposed to do. awesome!
I usually shift at 6,400 rpms and the limiter I set at 6,700 rpms. So I am thinking to have the nitrous turn off at 6,200 rpms.

Badas.sbird: I looked at that, but in the photo I wish I had left one of the nitrous timing feature buttons active when I took that screenshot. The nitrous was not on yet when the afr was getting goofy. In that screenshot above, the only time the nitrous/fuel was active was when the yellow rectangular data trace in the lower graph was up high. The light blue line that is in the upper graph and matches the same starting point as the yellow line, that is my fixed nitrous timing, and it has a longer box, because I programmed the fixed 32 deg timing to hold onto 32 deg for an extra .5 seconds after I am off the button.

-additionally, I finally changed my CL comp rate from 3 to 4. What this means is that I slowed down how quickly it makes changes. Setting 3 is pretty quick, which often times causes the sniper to react too quickly and overcompensate and then in-turn undercompensate its changes. Setting 4 slows its response down, for a less chaotic CL comp trace (hopefully). some people even run it at setting 5. I will try 4 and see if it adjusts slower and less drastically.

I took some screenshots of my fixed 100 shot datalog that I did a street rip on this past sunday. As mentioned, I rolled into it and only hit the button at about 4,500 in 1st gear. It revved up to where I had then set the nitrous to come off at (6,100) rpms and cut off, and then I shifted. I hit it at about 4,600 rpm in second, and off at around 5,800 well before the shift, and again in 3rd at about 4,700 to about 5,000 where I got off the button and off the throttle because I was on a public road. The AFR readings were a bit jittery, so I used the feature of "smoothing the datapoints together" to get a clearer picture of the results. It helped make more sense to me. see photos below. This is with an .050 nitrous jet and a .024 fuel jet. non progressive.

I took out some of the non-essential data traces. (the diagonal lines at the bottom, thats not a progressive ramp, thats actually the duration of the nitrous timer in the sage. Holley makes you set a stage duration in the tune file, so is et mine at 15 seconds. If I were to hold that button for 15 seconds, that line would just go diagonally upwards until it reached the top. I have it also set where if I get off the button, it just pauses the timer on the 15 seconds, instead of it re-setting).
- So the dark blue line, thats my SMOOTHED out AFR trace, and the green line that runs along with it, thats my target afr (which is 12.2 on nitrous and 12.8 N/A )



bottle heater arrived today. Hope to get time tomorrow to install it.

vorteciroc

I read through almost all of this Thread... there is a ton of typing in this Thread!

First off; I love the Car, It looks great!!! Especially the Engine Compartment... AMAZING!!!


I used to a do a massive amount of Nitrous-Oxide (Single Power-Adder) Engine Builds, up until about 10 or 11 years ago.
Obtaining the very large Tanks of Nitrous for my Shop Nitrous refilling-station became very difficult.
Getting any Nitrous became difficult compared to the years past.

The resurgent wave of Turbo-Chargers into the High-Performance "Street Car" world has all but wiped-out Nitrous use.
Turbo-Charger technology has been lacking until about 15 years ago.
Now, good quality, good design, aftermarket Turbo-Chargers are highly available, and highly affordable.

vorteciroc

I noticed that both the Crankshaft, and Camshaft Thrust/ End-Play were a little on the tight side.
I am wondering if the Engine Builder found that the Bearings used require a tight initial clearance...
Only to open-up during the Engine Brake-In?

Forgive me for forgetting some of the Information in this Thread... but it is packed with information.

What are the Static, and Dynamic Compression-Ratios?
What Fuel is being used?

Are you using 10w40 Engine Oil with the Main, and Rod Bearing Clearances that were set?

At what RPM speeds do the Peak Torque, Peak Horse-Power, and Red-Line occur at?
I would like to look at the Valve-Events... what are your Camshaft Specs, and installed Angle?
What are you using for Valve-Springs... are they shimmed within 0.050" to 0.060" from Coil-Bind?
What diameter Push-Rods are you using, and is there room to accommodate a thicker Push-Rod?

What are the Piston Rings made of/ Material... 0.020" Gap is most likely too small for regular Nitrous use over 50 HP.
You plan to try an use roughly a 200 HP Injection/ Shot... How much Ignition Timing are you removing/ retarding?
Are the Connecting-Rods rated for the Torque and Horse-Power that you intend to produce, while using the Nitrous?
Even budget Rods can handle the Nitrous Shot, when injected past the Peak Torque RPM.

I found out through many years of in-house Dyno-Testing that certain parameters can make Nitrous use SAFE for almost any Engine.
Piston-Ring Gap however, is one of the most important factors of "Safe Nitrous use".

I found that injecting Nitrous into a healthy Engine, is 99% safe when:
-RPM is over 3,000 RPM.
-Only under full-throttle.
-Using a Fuel with appropriate anti-knock.
-Using 1 step colder heat-range Spark-Plugs.
-Retarding 2-Degrees of Ignition-Timing for every 50-HP added.
-Past the Peak-Torque RPM (Higher the RPM the better here).
-But before the Peak-HP RPM.
-And Open-Headers.

I have successfully added a 300-HP Shot to a "Bone-Stock", healthy Vortec-350 Engine (with about 65,000 Miles on it)...
between 4,500 RPM to 5,600 RPM (Peak HP) over, and over, and over, on my Chassis Dyno (following most of the "Safety Steps" I Posted).

Good Luck and have Fun!

IROCZman15

iTrader: (25)

Cool, thanks for the advice. I know you had commented on my other build thread about the car/engine, but that was many months back. The nitrous has been my newest upgrade/adventure.
To answer some of your questions:
-I only use 93 octane Shell gasoline. No race fuel or additives, and they do not sell e85 anywhere near here in NJ
- static compression ratio is 10.5:1 Unsure of dynamic CR actually
- Engine oil I have used Valvoline VR1 20-50 since the day I installed the engine back 19 months ago in February 2020. Engine builder recommended it and that is what I have used durign every oil change. Even sent oil out to have it analyzed. I have a thread on this forum about it too if you wanted to read it, just search my username.
- As for the valvetrain questions you had, I think it is all listen in the photo above which has the hand-written engine build sheet info.
- I also will put the cam card and engine dyno sheets below as a photo.
- The rods are Callies Compstar H beams and even though I am certainly not an engine guru, I know that the bottom end is relatively stout and it was made clear to the builder that I planned on nitrous use on the engine for sure. bottom end info is also in the above engine build-sheet photo.
- I plan on following the rule of subtracting 1 deg for every 50 hp worth of nitrous. So 2 degrees for a 100 shot and 3or4 deg for a 150 shot. I really don't think I will end up spraying more than a wet progressive 150 shot. (It is not a race car, just a fun street car)
- I am glad to learn that 3,000 rpm is a safe enough number for my bottom-number for when to spray. I can set this parameter in the holley software so there is no "early-spray" mistakes...... In fact, I think I could even hold the button down and the holley software would not allow the solenoids to open until 3,000? maybe? That would be much more consistent than me trying to watch the tach needle sweep and try to then hit the button as it gets to 3,000.
- I do already have 1step colder plugs too; will need to spend some time learning how to 'read" or inspect them, that is important.

Again, since this is a street car, drag car, autocross car, show car, it has to do many duties. I am not looking to set astonishing times/speeds, but I do have my own personal goals that I would like to see on a drag timeslip.





I got the Nitrous Outlet Bottle header installed, wired, and tested today. It worked great and brought up bottle pressure after a few minutes. That was cool, and I am glad you guys encouraged me to get the bottle heater. I didn't grab a photo, maybe one day soon. Tomorrow I am taking the car to a local car show and for a good open-road drive afterwards too.

Here is the dyno sheet and the camshaft card that I mentioned:
-also, I do NOT plan on changing any engine parts on this engine for a while. Not going to swap camshafts, or file rings, or valvetrain stuff. Everything has been happy for 5,400 miles since I put the engine in during February 2020. Street car, street engine, with a little nitrous for some extra, thats all.

LB9GTA

iTrader: (1)

You should be pulling a degree for every 25hp of nitrous.

FYI, I pulled 7 degrees when I starting spraying a 150 shot just to be on the safe side, and then worked my way up

vorteciroc

^^^^^^^^^^^ I also agree with this.

vorteciroc

The Dynomometer Data appears to be from an Engine-Dyno.
Are the Engine Vacuum readings accurate?


The Engine Oil Pressure hangs in there, and does not fall off too far.

Does that Holley Sniper EFI System require that much Fuel pressure?
I have never used any of the Sniper Systems... just the high-end Holley Systems.
AFR is looking great!


I know that you are not looking to change any of the Engine Parts, but...
If you are using Roller Rocker-Arms, I would consider going to a higher ratio on the Exhaust Valves only (due to the single-pattern Camshaft).
Nitrous Engines really favor Exhaust Duration and Lift.

IROCZman15

iTrader: (25)

yes, I was mistaken, I looked through some of my old info and you guys are spot on with the "2 degrees per 50 hp" I used to rune that 100 shot on my tpi engine and i retarded the timing 4 degrees on the MSD digital6plus box. So I did it correct back then, but jumbled up my memory and what resulted was 2 deg per 100 hp instead of the correct 2 deg per 50 hp. Thanks for catching that.

Yes, that is the engine dyno of the engine just a day before it left the shop and was shipped to me. Fuel pressures there were higher than what the sniper regulates itself at, which is 58.5 -60 deg. Mine is usually in the 61-62 psi, and I have even swapped a replacement fuel pressure regulator after chatting with holley on the phone. It stayed the same, at 61-62 psi. On the sniper, the regulator is on the actual TBI unit right before the fuel return line. Oil pressure was good on the dyno graph there and still is pretty high, thats me checking with with my dash gauge and using an external oil pressure gauge on occasion which i thread into the block, just to make sure my dash gauge is reading correctly (it is)

as for rocker arms, while it may not been in my gameplan for the next year-or-so to open up the engine, something like rocker arms would be more practical for me to justify, so I will definitely keep that in mind. Something like a 1.6 ratio roller rocker? Again, not looking for more projects, but just maybe starting the wheels turning in my brain.


I am keeping an eye on the weather, and I think I am going to shoot for a Test and Tune track day on Sept 24th. Till then, a few car shows, street driving, and maybe a few more nitrous test hits on the street to examin plugs and datalogs. 2 deg-per-50 hp. Got it! Thanks everyone.

IROCZman15

iTrader: (25)

Sorry in advance for all the typing, but for a topic like this, I think typing out the details is important.
.....I haven't updated this particular thread in quite a while, but I have been updating my long-running car build thread pretty regularly, which can be viewed here:
https://www.thirdgen.org/forums/tech...g-install.html


back in the fall I did a lot of street testing with the nitrous and also a few dragstrip Test-N-Tune sessions. Car ran some 10.9x passes and a 10.87 at 124 mph which was its best of the year. That 10.87 was on a progressive 150 shot if I remember correctly. Actually, many videos, data-logs, and timeslips can all be viewed on the link above, just scroll back to the October 2021 timeline of the page.

During the winter, I built a much more capable exhaust system, and that can be viewed here:
https://www.thirdgen.org/forums/exha...ons-700-a.html
And I got a bigger(taller) set of rear drag radials. MT ET Street SS 275/60/15 which are 28.2" tall

This spring had a bunch of rain-outs at the local dragstrip, so I only have gotten over there for two race days. Once was a friday night and the track was cold and the starting line was not the best. Managed a 10.77 on a 125 shot. Just two weekends ago, I went for a nostalgia bracket race event and learned very quick that even running the car with no nitrous, all motor, I am not as experienced as some of those veteran bracket guys. I got knocked out in the first round. But I decided to stay for a few hours and got a chance to make a Test pass later on when the racing was slowing down for the day...

..I put in the 175 jets ( a .062 nitrous jet and a .032 fuel jet) and knew that it was unlikely the car would hook if I sprayed a "fixed" "non-progressive" shot. So I decided to be smart abotu it and ramp in the nitrous from 50% of 175 to 100% of 175 during a 1.2 second ramp. Instead of my N/A target ratio for AFR which is 12.8, I am having the sniper target 12.4 afr whenever the nitrous is active. I also have setup the ignition timing table to match the nitrous ramp table (see screenshots of the graphs below). The Nitrous was programmed to come only at 80% throttle but also to come on at 2,600 rpms but first gear is real quick so in reality it came on around 2800 rpms, and remember it was just 50% of 175 hp, so essentially about 87 hp or so). The car took it and went 1.44 in the sixty foot, which felt good. I tagged the rev limiter at the top of first gear for a split-second, so I lost a little bit of time there, and it turned off the nitrous because it breached the "high side" of my nitrous rev-limit window. It pulled through 2nd gear just fine and 3rd gear just fine too. THe first half of the track felt awesome, but still the second half of the track was relatively uneventful. See timeslip and split-times below.


Anyways, the goal for this car by the end of 2022 is to run a 10.5x pass, and my recent 10.601 pass tells me that it is entirely possible. I would also liek to see a trap speed of/at the 130 mph number, and that might be possible too, since I am currently at 127.7 mph. I am not sure the next tiem I am going to be racing at the track, as I have some important car shows and autocross events on my calendar, but next time I go, I am probably going to try the 175 jets again, maybe with a little more aggressive ramp? If I get my 10.5x pass, I might be satisfied enough to not bother with the 200 shot jets. However, i do have jets for the 200 shot and 225 shot, but I think 225 is probably not going to happen, because of the size/limits/flow of the actual nitrous solenoid itself.
-I did the math to try to figure out my best jet combinations using a 60 psi fuel pressure number to base my calculations on. The sniper datalogs show that I am close, but maybe a little too rich on the fuel jets. For me, this is ok, since I do not want to run lean and torch anything up. Since hte sniper is in closed loop when the nitrous is on, it just pulls the proper amount of un-needed fuel out from the tune in order to have the afr meet my 12.4 target afr number. Its usually pulling out between 8%-14% of fuel, and I am ok with that.

I guess I could also get a little more aggressive with leaning out my target afr number too? Maybe bring it to 12.6 or 12.7 instead of the 12.4? Is this safe? I know the jetting would change, and also Closed loop comp would change too. I have pulled some spark plugs after track days and from what I have learned about plug reading, the engine is showing that everything is safe and happy still with the 175 shot.

I figured that i would update this thread with actual results and info for all of you who gave advice during the earlier months as I was building the system. I would love the car to go a touch faster, mostly just trying to achieve my time-slip goals for the car, but I always have to keep in mind that this is a real deal true street car that occasionally plays on the tracks; I do not have a trailer, and the car has a full interior, while weighing 3,620 pounds in race weight with me in it while on the starting line. So, I think my goals are achievable, but if anyone has any advice, feel free to type it on in. Thanks!

Timeslip:



Video from a spectator:

Datalogs:



Nitrous settings datalog:



My jet chart:


Nitrous Stage settings:


timing table:


which matches the time axis of the nitrous progressive % table:





My VE table (for all motor)


My fuel flow table (for all motor)

closer view of higher rpms:

Orr89RocZ

iTrader: (20)

just be careful with that. A lot of nitrous guys don’t like or use widebands. I did on small shots and worked fine, but Def check plugs to verify. Theres some consensus that nitrous cars can fool o2 but thats usually with big shots and lots of timing being pulled. So i would try to make sure tuning is closer to desired, and play with afr for best mph, but low 12’s should be decent for something like that. My 383 did seem to run best around 12.2-12.4 on a 150 but it did also eat a plug ground strap on number 7 which with my intake manifold I suspect it was a leaner hole.

next is timing. Looks like you have a progressive timing retard vs time of run? By 3.8 sec you have 7 deg out rest of pass? I think you can easily add 2 back in and see how it responds. I think my best with a 150 shot was only pulling maybe 3-4 deg total. Smaller shots dont really need alot out unless edge of tune on pump gas already, but could try add 1-2 back in next hit if fueling looks good and should see mph go up 2-3

BadSS

I agree 100% with Orr. You need to be careful and back off the retard in small increments but l only needed to pull 2-degrees out when I was running a 150 shot plate system after using micro bits to enlarge the "stock" fuel jet. Keep in mind, I'm not suggesting you could get away with only pulling 2-degrees, my engine only needed 32-degree total to begin with. Each engine/fuel system is different, but I'd definitely back off the timing retard a degree at a time. Be sure to PULL and check the leanest plug after each run - that's what you're tuning for.

IROCZman15

iTrader: (25)

Orr89RocZ and BadSS, awesome!
Thank you for that advice! That's awesome to hear. I was pretty much following the rule of thumb for pulling a 2 degrees of timing for every 50 hp shot. So I figured that for a 175 shot, I would be safe and pull 7 deg out of the total timing (which is usually 34 deg at WOT) naturally aspirated. Not sure if I have mentioned it, but when i do make the nitrous passes, I am adding a little bit of the "Race Gas" concentrate to my fuel tank, to ensure no detonation. this stuff: https://www.jegs.com/i/Race+Gas/814/...caAs0TEALw_wcB
...so, in theory..it might be a reality that I can safely try pulling out less timing for the 175 shot. small bites like a degree of timing at a time. This could probably get me close to getting that 130 mph trap speed.

-as you mentioned, I have to be very aware of reading the plugs and I am still trying to figure out which cylinder is the leanest of them all. If my thinking is correct, the g-forces of the car and momentum would push the suspended fueling mixture furthest back causing cylinders 1 and 2 to probably be the leanest. Its the holley sniper TBI setup with the single plane edelbrock victor junior manifold.

vorteciroc

I also wanted to mention that it is common to pull some additional advance out, at the top-end of the Track...
Which when done for the correct scenario, improves ETs.

IROCZman15

iTrader: (25)

so, correct me if I am misunderstanding you guys, but it sounds like I could TRY to leave some more timing advance in the nitrous tune early and mid run, but then take more timing out at the very top end of the track ?

for example:
currently, as you can see in the screenshot above, I ramp the timing out beginning from 0.00 seconds and then by 1.2 seconds into the run I am pulling 6.5 deg of timing out and by 3.8 seconds, I am pulling 7 degrees out for the entire rest of the run...

future suggestion.. ramp some timing out , but instead of going as heavy as pulling 6.5 deg out by 1.2 seconds, maybe go with 5 degrees and see how it goes (checking plugs of course) then towards the end of the run, pull more timing out, say like 7 degrees? Am I understanding this right? I would set this tune up to follow the "time" parameter graph so since the car is running 10.60ish timeslips, I could let it ramp timing out at the launch, stay at 5 deg, and then right around the 9 second mark I could have it pull another degree or two?

i just want to make sure I fully understand his and the reasons/science involved before just blindly changing the tune and crossing my fingers for luck. I know to check spark plugs, that is a given.

vorteciroc

I was more so meaning that I would keep the Timing Retard for the Nitrous-Oxide in place as is...
Then try an additional 2-Degrees Retarded at the top of the Track, or even 4-Degrees or more depending on Results.

With the Engine turning so fast (high RPM towards the End of the Run) the Advance is not needed.


There are so many small changes (Tire Pressure, Front and Rear Shock adjustment, Anti-Sway Bar End-Link Adjustment, Ignition Timing Adjustment, Etc)...
that can be made that make for a good result, or add up to be a good result.

Good luck and enjoy!

IROCZman15

iTrader: (25)

Thanks for clarifying that vortech, and thanks to everyone else along the way for their suggestions.

Not sure when I am going to get back to the track, but I am planning on doing some street-hits in the coming weeks. So I modified my progressive nitrous tune file and the fixed nitrous tune file as we discussed.
* Both of these tune files are for a 150 hp wet shot and my total WOT timing is 34 deg advanced when naturally aspirated



Progressive 150 shot file: ( screenshots below):
-I changed the overall limit/duration of the nitrous shot to be 14 seconds long max just for some extra wiggle room, but the nitrous will only really be on for about 10.5 seconds since that's the timeslips the car is running at this moment in time. .
- at the hit, it is pulling 2 deg and starting the shot at 75 hp. It then ramps from retarding 2 degrees, to 5 degrees over the course of the next 1.2 seconds. It stays pulling 5 degrees from the 1.2 seconds all the way to 9 seconds... and then I pulled another degree of timing out from 9 seconds until 14 seconds, for a total of 6 degrees at the end of the run. Screenshot shows the "timing retard table" at the top of the photo and the "progressive control" graph at the bottom. (the timing degree values are in the white boxes of the upper table, and the seconds/duration is in the box connected directly below it). Does this look about right as to what we discussed?






Fixed 150 shot tune file: (screenshot below)
-this one is much easier, since there is no initial timing ramp or progressive ramp at all. in the beginning of the run. Some people have different names for the 'all in" shot, but I have tended to call is a "fixed" shot because all the values stay fixed at their numbers. However on this file now, instead of clicking the easy "run timing to fixed number" I decided to use the table to have the ecu pull an extra degree of timing out (as vortech suggested) around the end of the run when rpms are high. So the 150 shot sprays and it immediately pulls 5 degrees out, and stays this way until 9 seconds in to the run.. where it pulls another degree out, for a total of 6 degrees until the run is over which will typically be only 1.5 seconds later if I am still running mid-10's timeslips.





Comparison: (screenshot below)
everything about the base tune is the same, so driving the car around on the street with either of these tunes loaded in the car will be the same. I clicked the comparison feature on the holley software to verify. The only difference is in the nitrous and that is the progressive vs fixed shot's timing tables. You can see the blue line in the early state of the progressive table, but after the 1.2 second mark on the table, the two lines are stacked directly on top of each other. Thoughts?
I will probably leave the progressive 150shot file loaded in the ecu because a progressive shot has more hope of letting the car hook; the fixed 150 shot has not been kind to the tires on the street.