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I don't remember if MS has individual cylinder correction
It does, but I'm running a distributor not a crank + cam sensor.
A 2 bolt 400 block is a lot weaker than a 2 bolt 350. Sticky tires and hard launch can surely make the mains move around.
Originally Posted by Street Lethal
You know I had an aero deck hatch (minus spoiler) that I would have freaking given to you, I wound up junking it. Had no idea you wanted that for your car. I'm actually making a spoiler for the GTA, wait til you see what I come up with lol. I agree though. I keep looking at the GTA, then start thinking about the C4 I had, and I question why I ever gotten rid of it.
Should just sell both cars Joe and get a C7. Check this one out (last race);
It's the spoilers/wings that are hard to come by locally. They seem to all get broken somehow.
If I wanted a C7 I'd buy one. I have a lot of vehicles, but I've been kinda interested in 50+ year old stuff lately. My problem right now is I need more shop. Both garages at the house are packed. I've been going back and forth about building a large building out back, or selling the whole property and doing a new construction with a 4 car attached garage.
If I wanted a C7 I'd buy one. I have a lot of vehicles, but I've been kinda interested in 50+ year old stuff lately. My problem right now is I need more shop. Both garages at the house are packed. I've been going back and forth about building a large building out back, or selling the whole property and doing a new construction with a 4 car attached garage.
-- Joe
Oh God not you too lol. Between you and Steve with those old freaking cars lol. Guess I'm not there just yet. That's why I like the house we bought in New Jersey, nice size, nice size yard, but not too much that I have to worry about those additions, no time to even contemplate that stuff on my end. Just want to get a nice sized pool this year, redo the deck, and enjoy. Especially with e-town closing there's no more point to building anymore cars after this one, not to mention why I am geared more towards roll racing on the highway (in Mexico lol)...
MS can still at least read the air fuel in all eight at the same time though, no?
Oh God not you too lol. Between you and Steve with those old freaking cars lol. Guess I'm not there just yet. That's why I like the house we bought in New Jersey, nice size, nice size yard, but not too much that I have to worry about those additions, no time to even contemplate that stuff on my end. Just want to get a nice sized pool this year, redo the deck, and enjoy. Especially with e-town closing there's no more point to building anymore cars after this one, not to mention why I am geared more towards roll racing on the highway (in Mexico lol)...
MS can still at least read the air fuel in all eight at the same time though, no?
- Rob
What do you mean read the air and fuel?
It has MAP and or MAF for airflow input, and wideband o2 for EGO. I don't think you could do a cylinder trim without running sequential. On batch fire your firing based on the DRP. The trim functionality is for sequential fuel strategies, or at least it's an option only available when running sequential.
I was thinking of selling the Jetboat as I use my prop boat more often, but my sister was giving me crap because she likes it. But I've got a lot of stuff. The third gen is just one of many things.
I've got 1 horse left. If I can move him out this year, I can consider replacing the barn with a 60x40 building. The only problem is, in the winter I'd have to walk/drive down to it in the freezing cold. I like the idea of a 4 car attached garage.
It has MAP and or MAF for airflow input, and wideband o2 for EGO. I don't think you could do a cylinder trim without running sequential. On batch fire your firing based on the DRP. The trim functionality is for sequential fuel strategies, or at least it's an option only available when running sequential.
No, not having the MS perform any fuel trims, but still being able to see the air/fuel of each cylinder if you were able to install what you would need into the individual primaries. You mentioned you're not running a cam or crank sensor, but what I was getting at was essentially doing what the carb guys do, monitoring all eight cylinders individually, then making the similar changes the same way they would, but with injector size as opposed to jetting. It would work just fine. If MS could display the outcome of all eight at the same time, it would be a great tool to utilize while driving, minus the correction/trimming. That's why I asked if MS was set up to read all eight at the same time.
No, not having the MS perform any fuel trims, but still being able to see the air/fuel of each cylinder if you were able to install what you would need into the individual primaries.
I'm confused. How would I see the air/fuel in each cylinder? EGT? Wideband in each primary? I dunno what you mean.
Originally Posted by Street Lethal
Joe why would you say that, because of the limited tuning software for it? Or something else?
Strange engine that nobody really has any parts for, no machine shop wants to touch. Money pit.
Originally Posted by Street Lethal
Then what the heck are you worried about a 2 bolt main 400 for, blow it up lol...!!!!
... meanwhile I'm getting ready to blow mine up again, and that's okay lol.
I'm talking about reading 8 individual O2 sensors in each primary, then basing the change on the readings the same way the carb guys do, but rather than swap jets, swap injectors. Same principle, and way easier with your miniram. You never seen that before? Click on 5:56 minutes into it to understand what I mean. If MS can read eight at one time (not correct/trim because I understand your running the dizzy) but just read the air/fuel of each, it would be a great tool to utilize... but that is "if" MS can do that. I don't know if it can, that's why I was asking...
Click on and start it from 5:56 into the video to see partly what I'm getting at;
... meanwhile I'm getting ready to blow mine up again, and that's okay lol.
I'm talking about reading 8 individual O2 sensors in each primary, then basing the change on the readings the same way the carb guys do, but rather than swap jets, swap injectors. Same principle, and way easier with your miniram. You never seen that before? Click on 5:56 minutes into it to understand what I mean. If MS can read eight at one time (not correct/trim because I understand your running the dizzy) but just read the air/fuel of each, it would be a great tool to utilize... but that is "if" MS can do that. I don't know if it can, that's why I was asking...
Click on and start it from 5:56 into the video to see partly what I'm getting at;
- Rob
8 A/D's might be a lot, but you could probably pull it off with an IO extender. Sounds like a neat project but I'm not all that interested in that.
Funny, I was having a conversation about EFI the other day vs carb tuning. On a carb you adjust your accelerator pump, and jet it and call it a day. On EFI you have a ton of resolution on a table. It's very easy to have dead spots and such on a fuel map, whereas typically a jet will cover the entire operating range properly.
So what's the relationship between fuel percentage of a venturi vs a fuel map? Why is it that a static jet change works across the entire RPM range, but a fuel map must be manipulated in every region to work properly?
Now of course, this is over simplifying it. Carbs have idle circuits, primaries, secondaries and all of this is performed in the main fuel map. We make some educated guesses as to what 'region' of the map is each area.
But I wonder - should we be splitting this up into different maps?
The whole point of this conversation was discussing around tuning stock Delco ECU's. Let's say for example you do cam and heads on an LT1, it's not a matter of just increasing fuel across the board by a certain percentage. BLM's wil be all over the place everywhere, and logging, tuning, logging, tuning gets old quick.
On a carb app, you'd try a jet, maybe try another, and have it dialed in quickly. EFI has a ton of adjustability and you can be really granular, but when it also is a larger time investment.
That's probably why the better aftermarket self tuning stuff is more popular now, especially on carb retrofits. But if you have something like an LT1 Corvette, and you need PCM integration with the BCM/Dash, you can't exactly go ripping it out and going aftermarket.
In a nutshell that is really all it is for carb guys. Assuming adequate fuel pressure, a jet will give you your base fueling, your accelerator pump shot will give you your off idle, and your power enrichment will give you your wide open throttle. All of it can be dialed in mechanically with a wideband nowadays, no more of that ole timer tune by ear crap lol...
I stopped arguing about tuning when I realized people were simply arguing a "range" in which GM chose to go with for a specific horsepower. The resolution of those original systems were just enough for a 200 horsepower engine with a specific injector size, that is all they were really intended for. Raising horsepower with similar cam events only required upping the fuel pressure if duty cycle was kept in "range", that's it. But once you exceeded that range, but still kept valve events close to avoid overlap only required larger injectors and a re-calibration for those injectors, that's it. It's when people started changing valve events that threw everything out of whack, because now you have to not only change injector size if it exceeded the stock injector duty cycle range, but also alter the entire VE table because radical cams take in less down low, not to mention the need for a stall speed which people seem to forgot, and would complain about not being able to tune for off idle. When Bruce was still around, he would tell you that the ole LC2 ECM was hacked to death, and was more than capable of doing whatever you needed. People argued him, but here we are over ten years later, and stock '7148 ECM's are controlling nine second Grand Nationals just fine. He was right.
- Rob
Originally Posted by anesthes
8 A/D's might be a lot, but you could probably pull it off with an IO extender. Sounds like a neat project but I'm not all that interested in that.
Funny, I was having a conversation about EFI the other day vs carb tuning. On a carb you adjust your accelerator pump, and jet it and call it a day. On EFI you have a ton of resolution on a table. It's very easy to have dead spots and such on a fuel map, whereas typically a jet will cover the entire operating range properly.
So what's the relationship between fuel percentage of a venturi vs a fuel map? Why is it that a static jet change works across the entire RPM range, but a fuel map must be manipulated in every region to work properly?
Now of course, this is over simplifying it. Carbs have idle circuits, primaries, secondaries and all of this is performed in the main fuel map. We make some educated guesses as to what 'region' of the map is each area.
But I wonder - should we be splitting this up into different maps?
The whole point of this conversation was discussing around tuning stock Delco ECU's. Let's say for example you do cam and heads on an LT1, it's not a matter of just increasing fuel across the board by a certain percentage. BLM's wil be all over the place everywhere, and logging, tuning, logging, tuning gets old quick.
On a carb app, you'd try a jet, maybe try another, and have it dialed in quickly. EFI has a ton of adjustability and you can be really granular, but when it also is a larger time investment.
That's probably why the better aftermarket self tuning stuff is more popular now, especially on carb retrofits. But if you have something like an LT1 Corvette, and you need PCM integration with the BCM/Dash, you can't exactly go ripping it out and going aftermarket.
When Bruce was still around, he would tell you that the ole LC2 ECM was hacked to death, and was more than capable of doing whatever you needed. People argued him, but here we are over ten years later, and stock '7148 ECM's are controlling nine second Grand Nationals just fine. He was right.
Ok. I still don't know where the oil is coming from, but I can see where it's wet.
The edge of the deck, on the back corner of the block is wet. It pools there and then drips on the starter solenoid.
This actually is happening when running only.
There is no pressurized oil passages through the head. My first thought was that it was running down the back from the intake, but it appears to be dry. I spent an hour probing around with my inspection camera.
I can't imagine oil leaking from the head gasket via the oil return cavity, I'd expect it to leak water as well.
Maybe it is leaking from the corner of the intake and running down the head, I just can't see it. I use 'the right stuff' to silicone my china wall, so I'd be surprised if it leaked.
Coolant leak up front was just a loose clamp on the overflow - which reminds me. I have a catch can, and it's not vented. I wonder if that's a problem. the factory overflow is vented.
Trans was 2 quarts low. It's leaking from the tail shaft, and the shifter linkage. 2 quarts seems like a lot, maybe it wasn't quite full enough to begin with.
In a nutshell that is really all it is for carb guys. Assuming adequate fuel pressure, a jet will give you your base fueling, your accelerator pump shot will give you your off idle, and your power enrichment will give you your wide open throttle. All of it can be dialed in mechanically with a wideband nowadays, no more of that ole timer tune by ear crap lol...
I stopped arguing about tuning when I realized people were simply arguing a "range" in which GM chose to go with for a specific horsepower. The resolution of those original systems were just enough for a 200 horsepower engine with a specific injector size, that is all they were really intended for. Raising horsepower with similar cam events only required upping the fuel pressure if duty cycle was kept in "range", that's it. But once you exceeded that range, but still kept valve events close to avoid overlap only required larger injectors and a re-calibration for those injectors, that's it. It's when people started changing valve events that threw everything out of whack, because now you have to not only change injector size if it exceeded the stock injector duty cycle range, but also alter the entire VE table because radical cams take in less down low, not to mention the need for a stall speed which people seem to forgot, and would complain about not being able to tune for off idle. When Bruce was still around, he would tell you that the ole LC2 ECM was hacked to death, and was more than capable of doing whatever you needed. People argued him, but here we are over ten years later, and stock '7148 ECM's are controlling nine second Grand Nationals just fine. He was right.
- Rob
A stock ECM can support ten thousand horsepower. It doesn't matter, it's just commanding an injector pulse width.
The issue with a stock ECM isn't its ability to control a high output engine. You can write a college paper with a type writer, or even a pen. But it's a heck of a lot easier with Microsoft Office.
BTW Bruce thought the '7148 was crap. I used to talk with Bruce daily about this, he thought he '749 was the way to go, hence the $60 code he ran in his Buick.
Sadly can only be a few culprits at this point if it's not the valve cover Joe; intake gasket, head gasket, or a crack somewhere. Are your running MLS gaskets, and if so, did you coat them with copper seal?
As far as Bruce, I don't wanna say anything negative about his code, but the '7148 was definitely the way to go (it turns out), and the $60 was still a work in progress. The '7148 now acts like a mini XFI believe it or not, it's come that far thanks to Bailey and Marshall. I gotta give them credit...
Sadly can only be a few culprits at this point if it's not the valve cover Joe; intake gasket, head gasket, or a crack somewhere. Are your running MLS gaskets, and if so, did you coat them with copper seal?
As far as Bruce, I don't wanna say anything negative about his code, but the '7148 was definitely the way to go (it turns out), and the $60 was still a work in progress. The '7148 now acts like a mini XFI believe it or not, it's come that far thanks to Bailey and Marshall. I gotta give them credit...
- Rob
Felpro permatorque, so no sealant. There is no way it could be a head gasket or a crack, it would leak pressurized water long before it leaked gravity-returned OIL from the head. Think about how many water ports go through the head in that area. The oil drain is way on the valley side.
Chinawall is most likely culprit, but I couldn't find any signs of oil yesterday. Very odd.
Gotta give those guys credit, they love the hobby of hacking stock code. Working in memory and processing constraints must be very annoying.
Felpro permatorque, so no sealant. There is no way it could be a head gasket or a crack, it would leak pressurized water long before it leaked gravity-returned OIL from the head. Think about how many water ports go through the head in that area. The oil drain is way on the valley side.
Gravity returned? You're running a blower, and without knowing the compression levels of each cylinder, you could be blowing right by the rings pressurizing the oil pan, in turn pushing the oil out. Same motor with the turbo which didn't build boost at idle and you didn't see an oil leak. But now you're running a giant centrifugal blower and suddenly you're leaking oil. A crack under the valve cover in the cylinder head would leak oil, slowly without a pressurized oil pan, and pretty quickly with one. Again it's hard to say because its not in front of me, but if you have an oil leak in a specific area, it has to be one of those two things, a bad or leaky gasket, or a cracked part...
Originally Posted by anesthes
Gotta give those guys credit, they love the hobby of hacking stock code. Working in memory and processing constraints must be very annoying.
Meh, it's a hobby for them, and it saves the Buick guys loads of money. They look out for each other.
Gravity returned? You're running a blower, and without knowing the compression levels of each cylinder, you could be blowing right by the rings pressurizing the oil pan,
At idle with the BOV open? Doubtful. Not to mention I'd see pressure coming out of both valve cover breathers.
The motor has leaked oil since day one. I just had my mind on finishing other areas of the car. Now that those are done, I need to fix the leaks.
Well you see, that now that changes everything, you should have taken care of that oil leak before going through the process of the supercharger bracket and filling up the engine bay with stuff lol. Are you freaking crazy lol...?
Well you see, that now that changes everything, you should have taken care of that oil leak before going through the process of the supercharger bracket and filling up the engine bay with stuff lol. Are you freaking crazy lol...?
- Rob
I figured I'd get to it eventually. Now we are at eventually.
Hey Joe, how is that battery you're running? Was going to relocate the battery in the back because even with the new battery tray I made, it's hitting the wiper reservoir a tad. Then I had a few guys in the Import world recommend an AMS mini battery in which they swear by and never have any problems. That's when I noticed yours, can't tell if it's a mini, or you just have it clocked and next to the radiator. How is it secured...?
Hey Joe, how is that battery you're running? Was going to relocate the battery in the back because even with the new battery tray I made, it's hitting the wiper reservoir a tad. Then I had a few guys in the Import world recommend an AMS mini battery in which they swear by and never have any problems. That's when I noticed yours, can't tell if it's a mini, or you just have it clocked and next to the radiator. How is it secured...?
- Rob
I'm running a stock size battery. I bought a battery tray for like a '67-69 Camaro and welded it in sideways. Fits good. Tight but good.
I was going to say... its a full sized duralast red top. I relocated to the back for less than $100. Get a weld in allstar stray for less than $40 and weld $2 worth of 1"x1/8" steel, drill a couple of holes and bolt it in. Get some 0gauge and run it to the front and be done. I went for a larger group 78 tray I think so I can run a larger battery if wanted... but I run a stock autocraft gold with lots of room. Some silicone hose for breathers pushes any battery fumes from the vents outside the bottom of the wheel well. You will want the cranking amps, cleans up the engine bay and helps put some weight over the tires.
I was going to say... its a full sized duralast red top. I relocated to the back for less than $100. Get a weld in allstar stray for less than $40 and weld $2 worth of 1"x1/8" steel, drill a couple of holes and bolt it in. Get some 0gauge and run it to the front and be done. I went for a larger group 78 tray I think so I can run a larger battery if wanted... but I run a stock autocraft gold with lots of room. Some silicone hose for breathers pushes any battery fumes from the vents outside the bottom of the wheel well. You will want the cranking amps, cleans up the engine bay and helps put some weight over the tires.
That won't pass tech at the track though. I was gonna put it in the trunk, I have the wire for it, but my shutoff switch doesn't have enough amperage, and I need an NHRA approved box, and I lost interest lol.
That won't pass tech at the track though. I was gonna put it in the trunk, I have the wire for it, but my shutoff switch doesn't have enough amperage, and I need an NHRA approved box, and I lost interest lol.
-- Joe
true, i dont want to go to any tracks anymore and I think etown is closing by him so he wont have any tracks to go to lol.
Joe - I had the same oil leak this past summer had me scratching my head. after two set of new valve cover gaskets i finally noticed the valve covers barely touching the intake bolts/washers, which didnt apply even pressure to the valve cover. check and make sure their not bottomed out. Mine was "leaking" around the same spot you circled in the picture but i knew the head didnt have oil pressure in it so it wasnt possible - It was just running down the intake and then down the back of the deck/head surface which made it look like a china wall leak (Which is what i though i had)
Joe - I had the same oil leak this past summer had me scratching my head. after two set of new valve cover gaskets i finally noticed the valve covers barely touching the intake bolts/washers, which didnt apply even pressure to the valve cover. check and make sure their not bottomed out. Mine was "leaking" around the same spot you circled in the picture but i knew the head didnt have oil pressure in it so it wasnt possible - It was just running down the intake and then down the back of the deck/head surface which made it look like a china wall leak (Which is what i though i had)
Hrmm. So it was your valve covers?? Parimeter or centerbolt?
I'm running parimeter bolt right now, but I've been tempted to swap for some centerbolt covers.
I run center bolt's from proform - the bow tie ones. Also running a 4 bolt vortec style intake. I use right stuff on everything and ive never had a issue.
I relocated to the back for less than $100. Get a weld in allstar stray for less than $40 and weld $2 worth of 1"x1/8" steel, drill a couple of holes and bolt it in. Get some 0gauge and run it to the front and be done. I went for a larger group 78 tray I think so I can run a larger battery if wanted... but I run a stock autocraft gold with lots of room. Some silicone hose for breathers pushes any battery fumes from the vents outside the bottom of the wheel well. You will want the cranking amps, cleans up the engine bay and helps put some weight over the tires.
No junction block up front?
Originally Posted by customblackbird
true, i dont want to go to any tracks anymore and I think etown is closing by him so he wont have any tracks to go to lol.
Lucky for you, don't want that LSX beaten by a 305 lol...
It leaks at the corner of the head. It's actually not the china wall, but the very small space between the head and the deck. It appears the gasket doesn't go all the way to the edge of the head. I should have noticed this when I assembled it, but I guess not.
Pics for reference:
That's my actual 400 block before I had it machined lol
Lucky for you, don't want that LSX beaten by a 305 lol...
There's always Island and Atco...
- Rob
yes, I run a 3/8” stud as my junction block, they are like good for 250amps which is fine and $8 on amazon. I spice off that to a blue sea brand junction block good for 150amps to power all the small stuff like fuse panel, hookup for alt etc.
haha 305 vs 325 could be interesting... I don’t care as long as it’s a V8 and domestic. But my car isn’t exactly setup for drag anymore. No radials, street gears no more sfi rated belts yadda but it would be fun to see what they could do.
Wow Anesthes. I legit have 100% the same problem as you to a T. Dart SHP block. AFR 220's, Felpro head gaskets (1004). So you're saying it's coming from the top, not the bottom of the head. If that gap is causing the oil leak. Shouldn't there be the same gap in front of the motor/china wall too? Or is the gasket long enough in the front? Mine only leaks from the back. I've been trying to find this leak forever. I put dye in the oil, ran it, and was ready to pull the whole motor this spring to investigate. I’m 99% sure mines leaking from the same place. Hopefully like you said I can get some RTV in there so I don’t have to yank the motor.
Last edited by IROCThe5.7L; 03-06-2018 at 07:00 PM.
Wow Anesthes. I legit have 100% the same problem as you to a T. Dart SHP block. AFR 220's, Felpro head gaskets (1004). So you're saying it's coming from the top, not the bottom of the head. If that gap is causing the oil leak. Shouldn't there be the same gap in front of the motor/china wall too? Or is the gasket long enough in the front? Mine only leaks from the back. I've been trying to find this leak forever. I put dye in the oil, ran it, and was ready to pull the whole motor this spring to investigate. I’m 99% sure mines leaking from the same place. Hopefully like you said I can get some RTV in there so I don’t have to yank the motor.
One would assume the front, or both sides would have the same gap but I only appear to have the problem in the rear. I watched the oil running out with my inspection camera.
1014 gasket. (4.2" bore)
Can you get a camera behind there? It's a crappy spot because of the firewall. I might need to remove the distributor so I have enough room to clean and silicone it.
if not too hard i would pull the intake and reseal. you should be fairly liberal with the rtv in the corners, to tie the rtv into the head gaskets.
I thought about doing that. I just hate draining, refilling, and bleeding the cooling system. It seems like my 400 traps air pockets like nothing else, even with steam holes.
Speaking of, the heater core lines are a pain in the ***. I wish I could swap the heater core for an electric element.
One would assume the front, or both sides would have the same gap but I only appear to have the problem in the rear. I watched the oil running out with my inspection camera.
1014 gasket. (4.2" bore)
Can you get a camera behind there? It's a crappy spot because of the firewall. I might need to remove the distributor so I have enough room to clean and silicone it.
-- Joe
No camera. I am thinking about buying one though just for this. I went through some pictures of when I built the motor. And it looks like as you stated, just in the back the gasket falls short.
I am not sure how removing the intake would help. I laid a thick bead, especially in the corners. And laying the intake down and torquing it still wasn't enough to jam RTV down that small gap and seal it. Unless maybe before laying the bead, you take the nozzle and jam it into the corners and force the RTV down there?
I just don't want to yank this intake or motor-lol
Interesting. These gaskets were leaking coolant too. Not externally or internally, but it looks like it was walking over to the adjacent ports. Check out the stains on the gaskets.
This thing has been together for about 4 hours of run time.
I cleaned up the intake and there is some minor pitting. Maybe enough to cause this?
In other news, anyone have any leads on an ez-efi / fi-tech / sniper style 4bbl throttle body? The ez-efi units are still too much money, but if they have come down in price I'd love to run a 4bbl TBI with 4 85#/hr injectors on a dual plane manifold. I think it would be a much better setup for my low-rpm 400. The mini-ram is more suited for a high-rpm solid cam motor.
The sniper itself doesn't look like a bad system, and the software interface is nice, but functionality wise the Megasquirt is still miles ahead. $1,000 isn't bad for a complete throttle body, harness, and ECU but I don't want to lose functionality.
I'm running a large cap electronic HEI dizzy. I did this for simplicity of coil mounting.
Well, when I was taking it apart I noticed it has significant play in the shaft. Check out the video.
I compared it to a billet small cap dizzy I have and it's quite extreme. The small cap has a hair of play at the gear. Either way, both dizzy's result in some timing fluxuation, compounded by whatever slack the chain probably has. This really does make me think a crank trigger ignition is the way to go. One day I need to weld my 36-1 wheel to a crank pulley, and maybe swap back to my EDIS or run some LS2 coils on the valve covers?
I may run the small cap dizzy when I put this back together though. Still deciding. Comments?
yea heads are big for low rpm stuff.
That size engine with those heads, that intake, and a nice cam in the 250 duration range could hit 500+ whp and still be driveable.
have you considered going up a few pulley sizes on your blower and running an inlet restrictor? big torque gains down low but would be choked so it could only build so much boost. honestly though, most blower cars i have been in had no problem lighting tires up from a roll.
yea heads are big for low rpm stuff.
That size engine with those heads, that intake, and a nice cam in the 250 duration range could hit 500+ whp and still be driveable.
have you considered going up a few pulley sizes on your blower and running an inlet restrictor? big torque gains down low but would be choked so it could only build so much boost. honestly though, most blower cars i have been in had no problem lighting tires up from a roll.
It lights up the tires trying to back out of the garage. Power isn't a problem.
I'm not a huge fan of aggressive cams with low vac.
But at this point, swapping out heads would be a royal pain in the *** and not be worth the effort. I'd lose my shirt selling the AFR's because nobody on here has money, and those that do are building LSx stuff. And then I'd have to wait forever to get a good set of 1205 ports to replace them with.
If I was gonna go that far, I'd probably part the whole engine out and do up one of the many LT1's I have in the shop.
i guess what im getting at, is if low end torque isnt a problem, why are you in search of more low end torque?
why lose port injection to a tb setup?
why redo the charge piping and fight underhood clearance?
i just dont think any gains would be noticeable especially when you consider the converter probably flashes to 3k+ anyway. you would be much better served to put that money into a 24x/ls pcm setup with individual coils, imo.
the YSI LT1 car i have been working on has similar heads on a 388. it has put down around 690whp so far with 13-14# boost. ~9.0 compression, solid roller in the 24x-25x range. LT1 intake. it has the 24x setup on it.
i guess what im getting at, is if low end torque isnt a problem, why are you in search of more low end torque?
why lose port injection to a tb setup?
why redo the charge piping and fight underhood clearance?
i just dont think any gains would be noticeable especially when you consider the converter probably flashes to 3k+ anyway. you would be much better served to put that money into a 24x/ls pcm setup with individual coils, imo.
the YSI LT1 car i have been working on has similar heads on a 388. it has put down around 690whp so far with 13-14# boost. ~9.0 compression, solid roller in the 24x-25x range. LT1 intake. it has the 24x setup on it.
The LT1 is a good setup. On my Corvette with sequential EFI their is cylinder trims as you know, so it 'fixes' the distribution problems that plague these horizontal draw short runner intakes.
The Miniram is a bitch to tune with batch fire. I've run them on a few cars now, with different management systems and they are all somewhat temperamental.
Also, a blow through TBI is good because it atomizes with the boost better.
24x is difficult to do on my 400 block. I'm running a timing cover with built in cam button/retainer. It's an epic PITA retrofitting a vortec cover, crank wheel, etc on a older block with roller cam. You also have to ditch the double roller timing chain and go with a single roller. And you can't run a wide balancer.
I have a 36-1 wheel which I could weld to a crank pulley, but I'm concerned about balance.
Someone told me ATI sells dampers with built in 36-1 wheels. I couldn't find one specifically for a 400 SBC balanced to a 350 flywheel, just ford applications.
yea, i can see how that would be a pain/get expensive in a hurry on the older sbc. i have used a efi 24x system as well as a torquehead on an LT1 and they are pretty much plug and play. the torquehead is nice because it is adjustable outside of the engine. i had some issues with reluctor alignment with the behind timing cover setup due to variances in machining/crank/etc.
i was also pretty sure ati would do a balancer with reluctor on it.
02-26-2018, 02:11 PM
