T66 A/R? on 88' supra

[CarPsyco84]

here is a question for the pro's. My buddy was lookin for a good sized turbo to maximize his stock motor. The T66 seems to be a good pick for the 3L 7MGTE. My question is what A/R ratio would be best for power from like 4k rpm to like 7, 7500rpm, I was thinking .81 A/R but maybe even .88?

[niterydr]

http://www.suprasport.com/
Great turbo's!

[CarPsyco84]

thanx, thats even better, get to keep stock hook up to the turbo....

[Shane@DBPerformance]

.68 if you want it to spool by 4000-4500 with a P-trim exhaust wheel.

[CarPsyco84]

cool thanx for the input, Got another question as long as were on these size turbos, whats the difference between P-trim and Q-trim and what effect does it have I think i've herd that p or q-trim cause slower spool, but I don't know why....

[Shane@DBPerformance]

Q-trim is bigger than a P-trim, so it's a big laggier. The GTQ-trim versions aren't too bad though. A Q-trim over a P-trim can be worth worth up to more 50HP on a turbo that size.

[CarPsyco84]

So one can assume that Q-trim flows more air, and would be for like higher RPM hp than a P-trim, but you sacrifice spool time?

[Shane@DBPerformance]

So one can assume that Q-trim flows more air, and would be for like higher RPM hp than a P-trim, but you sacrifice spool time?

Yea. But even a Q-trim is not anything all that huge in the Supra world. It all depends on how much power you want to make, how high you can rev the motor, and how much lag you want to put up with. A T67 with a P-trim is capable of around 700whp, a T66 should put out around the same.

Here is how Shaun's 3.0l Supra with a T67 P-trim .68 A/R spooled on the dyno. http://www.boostlogic.com/parts/supra/info_supra_TurboKit67.html#dyno

[niterydr]

Yea. But even a Q-trim is not anything all that huge in the Supra world. It all depends on how much power you want to make, how high you can rev the motor, and how much lag you want to put up with. A T67 with a P-trim is capable of around 700whp, a T66 should put out around the same.

Here is how Shaun's 3.0l Supra with a T67 P-trim .68 A/R spooled on the dyno. http://www.boostlogic.com/parts/supra/info_supra_TurboKit67.html#dyno

Wasn't that 689whp on a very unhealthy boost spike? (like 35psi?).
Still spools damm fast!

[Shane@DBPerformance]

It was probably like 31-32psi, which is more than the VPC map sensor could read. It made 664whp at 29psi.