Dyno'd my 408 Camaro with TTi T76 Street Kit
i dont think you where listening when people where telling you that the type of turbo kit you have will make allot of back pressure even more with an 88
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So by looking at the graph, is it safe to say that would show a drive line problem?
I don't think 10 PSI from the current setup is much to ask for as long as I upgrade the valve train and transmission.
You still haven't told us what the compression ratio is on this motor..
And yes it can very possibly be a trans/converter issue, but like I said before its hard for anyone on here to try to guess because of all the other things going on with the car.
You mentioned that he blew the 4L60e, and used the converter from the blown trans into the new trans. That converter could have been contaminated. Have you checked the trans fluid?
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Mismatched or not, if you get it running right with this combo it will still be a fun car. I know someone local that put down 550rwhp through a TH400 and loose stall on 8 psi on a 408 and 76mm turbo. I think his compression ratio was around 11.5:1. I think they tried to up the boost and then it blew..
You still haven't told us what the compression ratio is on this motor..
And yes it can very possibly be a trans/converter issue, but like I said before its hard for anyone on here to try to guess because of all the other things going on with the car.
You mentioned that he blew the 4L60e, and used the converter from the blown trans into the new trans. That converter could have been contaminated. Have you checked the trans fluid?
You still haven't told us what the compression ratio is on this motor..
And yes it can very possibly be a trans/converter issue, but like I said before its hard for anyone on here to try to guess because of all the other things going on with the car.
You mentioned that he blew the 4L60e, and used the converter from the blown trans into the new trans. That converter could have been contaminated. Have you checked the trans fluid?
Not even sure my friend would know. I'll see if I can get in touch with him and see if he remembers. I have not checked the transmission fluid. Maybe I'll check that this week and see what it looks like. Thanks again for all of your help.
- Patrick
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Before you go and through parts, get good springs 1st thing then go from there. Next will be to check your transmission.
I don't thing you should have big issues with backpressure at that low boost or transmission issues. But, it's good to check your transmission and through good springs at the same time.
I don't thing you should have big issues with backpressure at that low boost or transmission issues. But, it's good to check your transmission and through good springs at the same time.
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You all think 918s would be enough, or should I go with some dual valve springs?
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At 2 psi, the poor thing hasnt even made it back to NA power level. See my sig 
It took 2 psi Just to get back to what my motor made NA. Thats all, it needs more boost
You guys really think that a turbine housing flows REALLY well? LOL! It doesnt! It works GREAT when it actually puts a positive pressure in the intake Thats the point.
It took 2 psi Just to get back to what my motor made NA. Thats all, it needs more boost You guys really think that a turbine housing flows REALLY well? LOL! It doesnt! It works GREAT when it actually puts a positive pressure in the intake
Thats the point. Thread Starter
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I see your point...one thing that still baffles me is that I normally see ~5psi on the street in 2nd gear. I have verified this with my tuner who looked at my logs and said my MAP would peak at 140kPa in second gear. We never really took it into 3rd because by that time I'm going a little fast for anything on the street. Got to be something with the drive line (as well as the other things mentioned) that is causing the strange HP/Torque curves.
I should of had him do some data logging while it was on the dyno. That would of really helped to see what was going on.
I should of had him do some data logging while it was on the dyno.
That would of really helped to see what was going on. 
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Feedback 1. Check for fouled spark plugs.
2. Set gap low (try 0.025") then move up until it starts blowing out under boost.
3. Replace valve springs with Patroit Dual Xtreme.
4. Monitor Backpressure or Get Turbo Specs (eg.A/R).
5. Look at drive line.
2. Set gap low (try 0.025") then move up until it starts blowing out under boost.
3. Replace valve springs with Patroit Dual Xtreme.
4. Monitor Backpressure or Get Turbo Specs (eg.A/R).
5. Look at drive line.