83 Crossfire TA

iTrader: (2)

heh... my wife already names my cars with "stripper" names...

ZZ3Astro

First day at the drag strip. I am having a problem getting the TPS to 100%. My first pass averaged 55% with a peak of 61% and it went 7.94. I got a 75% pass and when 7.74. Finally got an 80% average and when 7.71. Totally my fault as when my friends drive it they find 100%. I even moved my seat up! Dunno

My best 60 foot was 1.84, so a good bit of room for improvement if I went with some sticky tires instead of firestone radials. Pretty sure I was the only car any where near 7's without sticky tires so that was cool. Sometimes I get lucky and get into the 1.7x short times but not today. Once it spins now, it's over.

MPH was lower than I expected, but an improvement over the stock engine by about 5 mph, at 92.5. I'd hoped so see around 94. Time to upgrade the turbo. I can turn up the boost but I don't think it's gonna make much more power.

Looking at my short times, the 7.71 on a 1.84 might as well be a 7.50 pass because low 1.6x is more than possible with sticky tires. I don't think 1.5x would be a problem either. I'm practically idling off the line and the second half of the sixty is where the time is coming from. Anyway, 7.50's is about as much as I expect this ebay 60mm to support so I'm pretty happy with today's results.

Here is a video of my best run: http://www.youtube.com/watch?v=57Zzw...&feature=inbox


Also, I went to a car show (and lost big time) about 100 miles away. On my return trip I averaged 19.5 mpg! Goal met!

Orr89RocZ

iTrader: (20)

Dude, 92mph is a mid 11 second car! My 383 went 11.47 at 118-119 and trapped 92-93 mph in the 1/8. 1.5x 60's. If you get there, you should find 7.3-7.4 1/8's

noboostnogo

iTrader: (4)

Cant see the video but sounds like its hauling a$$ right now, i went 7.5s with a 1.6 60ft, i forgot my mph i ended up trapping a 11.8 at 112mph but my old setup was really bad at anything over 4k rpms, so you should deff be in the mid to low 11s. Good Luck

ZZ3Astro

Ok so I'm trying to figure out why I'm losing oil pressure at 4000+ rpm, only during acceleration (or at least high engine load). It occurred to me tonight that my oil pressure sender is on a T with the turbo oil feed. I'm not sure how turbo oil demand changes under various conditions, but the drop in pressure could be tied to something going on with the turbo during high boost.

My options are:

Try brake-boosting to eliminate the 'oil running up the rear of the pan' theory. If brake-boosting produces the problem in absence of acceleration, is there some (bad_ engine condition that can cause sudden increased oil demand beyond what a typical pump can provide?

or

Hook the oil pressure sender to the port above the filter instead. If the pressure doesn't drop there, it's obviously the turbo. If it does drop, it's obviously something internal with the engine.

Pressure from the current location varies from 20 to 50 psi. Pump is the stock ZZ3 (not high volume nor modified for higher pressure) so it doesn't have increased oil demand or anything. Engine rpm is relatively low, not exceeding about 5400 and the problem starts closer to 4000.

Might have to pull the engine (or do a pita in-car dropping), which totally sucks.

Drac0nic

Oil pick up distance to the pan?

ZZ3Astro

I just went back and watched the video of the final assembly. The pickup is definitely as close to the bottom of the pan as it can get. Judging by putting my mouse cursor on the pickup and watching the pan installationt's less than 1/4 inch and might even be hitting the spacer bump on the bottom of the pan. Of course it is at the forward portion of the 'drop' of the pan as it is a stock pickup.

ZZ3Astro

Further testing is not looking good for keeping the oil pan untouched. Tonight I brought it up to 4500 and brake boosted it - no problems with pressure dropping so that eliminates an issue with the turbo at high boost (since the oil feed and pressure sensor are on the same T).

Only thing I can come up with is the oil sloshing to the rear of the pan, or the pickup has moved somehow. Doesn't make a lot of sense though except that my car is pulling decently at full boost.

83 Crossfire TA

iTrader: (2)

huh, how low is it dropping? What kind of pressure gauge are you using?

ZZ3Astro

Just the stock gauge but it has always been reliable (consistent at least). If it's 50 psi at 3500 it's down to 30 by 5000 rpm if accelerating at wot. I'm out of it by then so no idea how low it will drop.

Orr89RocZ

iTrader: (20)

Some kind of oil drain back issues? Either in the motor or in the turbo drain lines?

Definately want 10psi per 1000 rpm or so... 30 at 5K is too low.

ZZ3Astro

Seems plausible but Im not sure what kind of engine oil return issues I could be having with what is ultimately a stock sbc in every way that matters. Low rpm, stock pump, stock pressure & volume.

The turbo oil system is unchanged from the previous engine so drainback should be the same. I don't see signs of smoke or oil consumption. Probably the only variable here is that I'm running Synthetic 10w/30. I never ran synthetic in the old engine, and just I poured whatever cheap oil I could find into it - yes even DG oil! Usually it was 20w40 or 20w50, which if anything would have been more difficult for the drainback system to work well.

I was unaware of any problems until I changed the 10w30 conventional to synthetic at about 450 miles. It is Valvoline SynPower 10W-30 and the filter is a Bosch DistancePlus. I kept my eye on the oil pressure quite a bit during break-in, but also I didn't spend much time in sustained high rpm boost until after the oil change. Really though, since I have good pressure while not accelerating, I just don't see where the filter has any effect.

All I know is it would suck to drop the pan and find nothing wrong, or worse yet replace the pickup and pump only to still have the same problem afterwards.

Orr89RocZ

iTrader: (20)

Could try a thicker oil or go back to the non-synthetic stuff. But I wouldnt expect oil pressure loss at higher rpms with either of the oils.

ZZ3Astro

Went back to non-synthetic 10w-30 and a Pure One oil filter. As expected, no change. One thing kind of bothersome is how dark my 200 mile synthetic oil looks already. Not black but certainly not nice and clear like I expected. Hmmmm.

I bought a cheap oil pressure gauge tonight. I'll hook that up the the fitting above the filter tomorrow night and see what it says.

ZZ3Astro

Dyno night tonight. It's about 80 miles from here so as long as it survives the drive, I should have new numbers tonight. Also I'm going to pay close attention to the oil pressure as there won't be any acceleration to affect the oil in the pan.

Last night I got on it good and the pressure fell to around 35-40, I let off and eased back into the gas and the pressure stayed up around 50. Anyway we ended up around 130 mph. When it shifted into OD around 120, it sank us into our seats pretty good. It really pulls best in the bottom of the gears in true tpi fashion. I was pretty surprised at the amount of pull at 120+.

Hoping to see at least 340 rwhp and 425 rwtq. Still on the 60mm ebay turbo for now and about 13 psi.

ZZ3Astro

Weird results from this dyno. I also noticed other cars' curves looked similar. While the test rpm started at about 3500, peak HP and TQ were both exactly 4750 rpm with a pretty quick dropoff to 5100 which then levels out until 5500 when I let off. Part of this is probably because of the stall converter, but my torque peak certainly occurs well below 4750!

So as odd as this may sound, my peaks were:

346 rwhp @ 4700
383 rwtq @ 4700

I was expecting to see around 350 rwhp based on the ~430 crank hp required to run 92.5 mph in the 1/8 with my car. The reason it was a bit low? My AFR was 10.2-10.4 during both pulls! Funny thing is the duty cycle was higher as well. With no change to the tune, on the highway the AFR is 10.9-11.0 at full boost. Difference in load? Either way, if I tuned it to 10.9 for the dyno, it would have easily been 360 rwhp, so I feel pretty happy with the results. Not happy with the tq recorded but I know the peak occurs well below the rpm where the dyno was able to show power being made. I have NO shortage of torque in this thing!


WEIRD dyno sheet

ZZ3Astro

Almost forgot, got in a little race last night. I was literally 5 blocks from being home, crossing the main highway when a brand new GT-350 with temp tags crossed in front of me. They were just staring and smiling like they knew they owned the streets. I decided to turn and follow them. They immediately slowed a bit below the speed limit so that I would pass them. As I passed by, it sounded like a nitrous purge but I'm pretty sure it was a manual transmission ooops sound. He didn't hesitate to hit the gas and immediately fendered me. I just left it in D and floored it and they instantly disappeared from my view. It was over in 2 seconds max. Awesome end to a cool night!

Anyway I just dug out my previous dyno sheet from this place. It was two weeks after I put the stall in and two months after the intercooler. My numbers were about 50 lower for tq and hp than last nights, with the exact same ~4700 peaks. So I conclude that this is a result of the uncanny relationship between inertial dynos and stall converters. The track numbers are the only ones I worry about anyway.

Drac0nic

Intertial dynos are known for producing "off" numbers with turbo systems. Can't load em well or something. Probably why your AFRs were odd too. Just something to keep in mind.

Orr89RocZ

iTrader: (20)

exactly...never loads the same so the airfuel on the dyno will be richer. Always tune slightly richer on the dyno and on the street, it will lean out.

Curve is weird, you sure they calibrated everything right? tq and hp cross at 5252.

freaky

nice kill at the end of a night .

ZZ3Astro

Ok turbo experts.. I decided I didn't like the power I'm getting at 13 psi and that I wanted to see what the IAT's are at with 16-17 psi. As my wastegate spring is already as tight as it goes, I put a vacuum T in line and a small valve to bleed off boost. I worked my way all the way to unplugging the line from the wastegate entirely. It would not go over 15.1 psi. IAT did climb but I can only measure it on the cold side of the intercooler. The increase was only 1-2 degrees after several seconds of boost. My impression of a 'maxed out' turbo has always been that boost can go higher but the temps will climb sharply. Further thinking while driving around tonight concluded that if my engine is asking for more air than the turbo can provide, boost pressure would fall with the increasing volume.

Of course a turbo upgrade has been in the plan for this new engine anyway, but I wasn't sure how the limit would manifest. If I'm thinking right here, I'm already in the red zone and performance would increase immensely at the same boost level with a better turbo. I was told to expect a sharp increase in IAT as I approach the max on the turbo so this is the one variable making me scratch my head in deciding its time for that bigger turbo.

Any other input is appreciated!

Drac0nic

Interesting. I'd almost say a turbine size housing except I thought you were on the small order. What exhaust are you running through? If it's a full exhaust you may want to measure back pressure at the down pipe.

Orr89RocZ

iTrader: (20)

It still may be pretty efficient and not increase IAT that much with 3-4 psi more, but the real question is, does it make any more power with the higher boost? Maxing out a turbo would imply air flow limit has been reached, and that wont increase with higher and higher boosts, so if power dont increase with higher boosts then your tapped. IAT should increase as efficiency falls off the map, but on compressor wheels, the hottest air temps occur closer to surge, and coolest temps are at choke for a given speed. Choke flow temp may be higher than normal efficiency range discharge temps when at higher compressor speeds. As speed increases, so does temperature at choke point, since pressure would increase.

So it all depends where you are at in the map

ZZ3Astro

One problem with these Ebay T70's... no map to look at!


Anyway, to me, the engine isn't making as much power as it should be for 13 psi but when I change the boost level I can definitely tell a difference. Tonight's 15 was pretty spunky actually. But at 15 this thing should be making at least 70% more power than na. I would think my engine combo under a tpi na would produce about 320 hp. Should be north of 500 crank hp.

Will definitely look into the downpipe pressure. I'll just unbolt it at the front of the cat and see what happens.

ZZ3Astro

This morning I unbolted the exhaust and went for a spin. I saw a peak boost of 15.5 psi vs the 15.1 from yesterday. After discussing the situation with Pete at Precision Turbo, he said to him it sounds like the turbo is just out of capacity. With the mounting limitations of my setup, he narrowed it down to the PT-6766 with a .96 AR. This turbo has the same mounting specs as my ebay T70 but with a 900 hp capacity. Since I am only looking for 625-650 at the crank, this should spool quickly and not be overworked. He really wanted me to go with a 71mm but said my stated goals would not be a problem at all with the 67.

I called the local dealer up and got it ordered this afternoon. If my car still acts up, I'll build headers next. It shouldn't have any problem making the power with the current setup though.

Orr89RocZ

iTrader: (20)

yeah a single 60 may be maxed at that level. Its hard to say. I was pushing 640whp with pair of T60's and going from 12 to 17psi only gained 50whp but it was running very rich on 17psi. But at the track 12 to 16.5 psi picked up about 5mph so not sure what to think there. Everyone told me my 60's were good to 500whp and I was only doing low 300's each. I went to T70's and didnt gain anything...actually went slower and slower on same boost. No idea what happened.

Going bigger is not always better but I think you could use a better designed compressor wheel. That 67mm should be the ticket.

Ofcourse, TPI swap to a better intake would pick up some power

ZZ3Astro

Hard to know for sure... I just feel like at 14 psi I should be seeing a bit more performance. Efficiency on my stock engine was pretty decent. Running about 11 psi ntercooled, it produced 299 rwhp. Assuming 18% drivetrain loss, that was 365 crank hp. With an original 230 crank hp NA, that is a 59% improvement with 74% (11 psi out of 14.7) of 1 bar boost. So about 85% efficiency of boost to hp increase.

If the new setup was producing only 300 crank HP NA (it should be at least 320) it should dyno at 246 rwhp NA. With 14 psi of boost, at a very conservative 75% efficiency factor, it should dyno at least another 175 rwhp for a total of 421 rwhp. That's about what that white 5.0 put out right after me. In fact with this 224/224 cam and the pocket porting, I think 330 hp isn't far off the mark. And certainly 400 ft lbs at the crank based on other stock tpi NA builds I've seen. Taking the same factors from above, torque should be in the 500+ rw range.

Something is definitely off.

Orr89RocZ

iTrader: (20)

Well your dyno chart is kinda funky to begin with. HP/Tq dont cross right and doesnt look like you started the run early enough to see peak torque. I wouldnt sweat it. Its running hard at the track which is what counts

ZZ3Astro

Just a rough measurement of the endplay in my old turbo shows at least .008" end play! Last time I checked (just by pushing in and out, not with a dial indicator, it had no noticeable play. I'm pretty sure that was done while the engine swap was going on. I'm wondering if the drops in oil pressure (never goes below 30 psi) in this new engine could be sending air to the turbo oil system and causing rapid degradation of the bearings. Would hate to have that happen to the new turbo. I haven't been as alarmed by the drops lately because all of the accumulator systems I've researched general don't activate above 30 psi. Usually the pressure 'only' falls to about 38-40 psi. I've never seen it below 30.

Radial play is also looking pretty concerning. No contact of the compressor blades yet but won't be long. I double checked some of the manifold bolts tonight and they were not loose. After seeing this I'm pretty sure the source of the limited boost is revealed.

Drac0nic

Vinteresting. If it was too small and you were over spinning it there may be something to that as well. Just throwing it out there.

ZZ3Astro

Well the PT6766 is on.

FRUSTRATED is all I'm going to say for tonight's test drive.

ZZ3Astro

The results are underwhelming. Everything about the new turbo itself is great. It barely fits with about 1/4" clearance between the compressor houseing and the wastegate. The sound is AMAZING. It spools up early and stays spooled longer. The BOV is completely out-classed now. The wastegate should also be upgraded but that will require some reworking because of the limited clearance. As a result of the wastegate sizing, the turbo over-shoots on boost to 14 psi, then falls back to the wastegate setting (which will ultimately be over 14 anyway).

Driving results? Much more responsive on the low range. A brick wall up top. This was after a lot of tuning to add fuel through-out the boost range. Performance at 11 psi was silimar to the previous turbo at 15 psi but no where near outstanding. Lacking any better options, we turned up the boost (which ended up being 17 psi) to see if performance could be found. Instead I found a new brick wall... fueling issues once again. How a Walbro 255 in-tank isn't enough to feed a less than impressive amount of power is beyond me. Injector duty cycle was over 100% at 17 psi and AFR was high 12's. Turned the boost back down to about 12-13 and I can maintain a 10.9 but no way in hell I could be happy with the power.

Yes it hauls but no it's not scary at all. Not gonna make it to 6.90's with this and I cannot figure out what the bottleneck is. Today I'm going to measure exhaust manifold pressure and eliminate the air filter to rule those two things out.

Orr89RocZ

iTrader: (20)

Without dyno or track times its hard to tell whats going on but if the turbo runs hard at 11 psi compared to the old setup with 15, thats a victory. When I swapped to larger turbos thinking I had a small turbo for the setup, i went slower.. required more boost to run same times.

I'd start looking at blowing thru the converter with higher boost. Is it a stock converter? is tranny slipping? I forget what you are running. Also look at opening up TPI to a short runner setup. Siamese it or something to gain some rpm.

Single pump should be good to 550whp+ depending on voltage. thats enough for 6.90's believe me. It sounds like the motor is making power but just not getting it to the ground thru the tranny. Makes me think converter but I may be out in the weeds here.

ZZ3Astro

I'm wondering about the trans too, but I don't think it's slipping at all. It's a vigilante 9.5" 2800 lockup converter in front of a pro-built 700r4. The build is supposed to support 675 hp. I can hear the turbo 'despool' when it starts feeling flat. Very strange for sure.

Orr89RocZ

iTrader: (20)

Its not floating the valves is it? I'm not really sure what a turbo sounds like that "despools" but are you saying it sounds like its not spinning as hard as it flatlines? The whistle sound fades or changes in tone?

have you tried it without an air filter/intake pipe on the turbo?

ZZ3Astro

Definitely not floating, it can't turn that high anyway but I rarely go past 5100 on my street driving tests. I drove it today and have discovered my friend last night wasn't very reliable in conveying the activity of the KPA gauge. It was only sustaining 8 psi today and last night I was under the impression it was holding 12-13 psi. It does spike to 14-15 then falls off to 8 psi. Well that would explain why it slows down, in addition to the leaning issues when it goes above 13-14 psi. I'm running a new wire/relay directly from the battery to the pump to see if that helps at all. Air filter test is during tonight's dinner run!

daverr

iTrader: (1)

did you check the cold side for leaks??

junkcltr

iTrader: (1)

Wire from battery to pump bypasses the oil safety switch. If you are OK with that then run the wire from the output of the alternator to the pump, not the battery to the pump. It will give a higher voltage. Install a fuse if it doesn't already have one.

What are the differences in the turbine wheel size and A/R?

ZZ3Astro

K I didn't get around to the air filter test. It is first and foremost a fuel delivery problem at this point. At 14 psi we could only tune it to 11.3-11.5 afr in third at 93% duty cycle. The lighter loading in 2nd puts it right on top of 10.9. I'm feeling much better about it right now from a 'performance improvement' standpoint. I broke traction in 1st, 2nd and 3rd, having to let out in each and then back in. This on a road that I have traditionally not had a big problems with traction on. Basically it runs super strong until higher rpm with high loading (third), then it goes a bit flat and the afr increases into the 12's.

I'll work on the fuel pump power wire this week and see if I can get that delivery under control. At this point, pulling the air filter is only gonna make the afr worse if it's holding any air back, so I'm gonna hold off on that test.

Old turbo is either 60 or 61mm compressor and not sure on the turbine but its less than 70 and more than 60. It was an a/r .96

New turbo is 67mm compressor with a 66mm turbine and also a .96 a/r. But wheel size aside, there is no comparison between these wheels. The hub size is much smaller on the PT so it has a greater flow area. And the blades are swept, so they are quite a bit more substantial than the ebay turbo. They have the same T4 flange and 3" exhaust outlet, but the 2.5" charge outlet is cast thinner and slightly larger o.d. make the actual opening quite a bit larger.

ZZ3Astro

Well I'm back to square 1 once again. The car is simply not maintaining sufficient fuel pressure, even with a new 12 gauge wire going directly to the battery. I wasn't thinking clearly about the ramifications of the fuel pressure issue. Up until tonight I felt ok as long as the AFR was in the safe range for a given boost.

Here is what I believe to be going on, and the results:

The fuel pressure fell to 22 psi tonight while at 14 psi boost!! The injector duty cycle was at 92% to maintain a 11.9 AFR. These are 65 lb injectors. That shows only 8 psi of relative fuel pressure at the injector nozzle! The fuel cannot be atomizing sufficiently. This is likely leading to unburnt fuel reaching the manifold and turbo. This is creating excessive heat (I have some heat shielding tape on the AC box that is melting!) and very likely lead to the sudden wear on the ebay turbo. The other thing is if unburnt fuel is exiting the combustion chamber, its power is not being put to work.

This would explain why the car runs very well at low boost and suddenly hits a wall, even though the AFR is correct (by the time the mixture reaches the O2 it has fully burnt).

I just can't understand how the 255 isn't handling this engine. My friend uses them all the time on turbo v8's making a lot more power than I'm making. Worried that I'm going to spend another 200-300 for a pump upgrade and run into the same issue with it.

Orr89RocZ

iTrader: (20)

Whats the pump voltage doing? Heat affecting alternator at all in its ability to charge battery?

project89

iTrader: (1)

like i tell everyone else goto a areomotive 340LPH pump they are only 20 bucks more then the walboro 255lph. though in ur case installing a second walbro wouldnt be a bad idea.

u have to rember as fuel presure increeases the pumps flow decreases, @ 12 psi 55psi fp the walboro only flows 180 ish lph i belive

Orr89RocZ

iTrader: (20)

Still, I think it should be good for more power than he has. I know i've seen guys make 500+whp on a single pump even with boost.

ZZ3Astro

No problems starting or otherwise. Even before I re-wired the pump directly to the battery, I saw at least 13 volts at the pump at all times other than starting.

My friend has that tpi 383 single turbo that put down 600 rwhp with the same pump and injectors that I have. I'm not even at 450 rwhp and my pressure is barely enough to keep the engine running.

Orr89RocZ

iTrader: (20)

Seems weird man. Fuel filter clogged? I am not sure what would be causing the poor fuel pump performance. regulator working right?

ZZ3Astro

Brand new Wix filter which replaced an almost brand new whatever brand filter. Two stock regulators swapped in with no change. Of course I also recently changed the pump, during which time I made sure the returning fuel doesn't spray directly into the sock. Plenty of gas in the tank during the testing.

daverr

iTrader: (1)

try a different fuel pressure gauge.

project89

iTrader: (1)

hook up the fp gauge and turn the pump on take a reading, then pinch of the return line were its rubber and see what the pump deadheads at. if fp dosent jump up pretty good the pump is weak

junkcltr

iTrader: (1)

Is the small piece of rubber hose from the pump to sender real submersible fuel line and not just EFI line? Did you check it for cracks & deterioration? Plain EFI line will crack when submersed in fuel.

Have you checked your other rubber lines? How old are they?

Is the diaphragm in the AFPR cracked?
Are you getting boost pressure to the AFPR (no check valve, good line, etc)? Actually checked the line for blockage?

ZZ3Astro

Already have had a separate mechanical gauge hooked up, but more importatly I'm running 100% duty cycle to 65 lb/hr injectors and I'm going lean. It should be around 800 hp for that to happen!

I just replaced that hose with a special submersible high pressure fuel line when I put the new Walbro in last month. I also inspected the old hose from the first Walbro and it was in good shape.

The only other rubber lines are the ones up front, and I had the fuel feed line cut in half and had flare fittings installed so I could connect to the rear of the fuel rail (to get around the restrictors in the stock feed location). I actually have the original feed plus the rear feed (to the cold start injector fitting) so there are no chances of feed issues up front. We thoroughly checked the inside of the feed hose and it looked like new inside. I didn't cut the return line but if anything a restriction there would improve things

Only way the FPR could be the problem is if two in a row have the exact same problem. It has a boost/vac direct line from the upper plenum to the FPR. I even put a zip tie on the FPR side so it wouldn't blow off. I would say maybe the factory one can't handle boost but my friend has done a number of TPI engines with more boost than I have and has never used anything but a stock regulator. Before I replaced the pump and all, I had changed the regulator, in addition to testing it with the boost reference line disconnected. Nothing changed with the problem of losing pressure up top.

I would love to test the main fuel line for restriction but how do I do that? The only two ways I can think of are both pain in the azz things.. either cutting the hard line and putting a fitting with a pressure gauge in the back, or running a whole new line to see if the problem goes away. Any other ideas much appreciated!

At this point I'm pretty much out of ideas. I can replace the pump with a bigger one. Since the pump I already have is sufficient for the job, I am risking $200-$300 for a larger pump that may have the same problem. I can replace the stock fuel line but there are plenty of examples of people using stock third gen lines to make tons more power than I ever wish to make. I've already done everything else. Where do I start?