Just got the run files from our tuning session at Batlground two weeks ago. (Their Supra just ran a 8.56@170mph in street tire class last week btw)

Car's specs are:
T3/60-1 Turbo
Wastegate controlled boost (5-7psi)
370CC injectors
BEGI FPR
Greddy E-manage
3" test pipe and exhaust
Stock auto w/ VB Mod & cooler

Car doesn't see 7psi except in 3rd gear right now b/c of the wastegate opening too early so it's a bit harder to get off the line than that torque curve would suggest. Plan to spray a 30 shot to fill out the bottom end some more and possibly a custom intake manifold to get some more hp on top. It'd be nice to hit 350whp w/o exceeding 7psi.

 

Wow nice! I would think about getting VI to help the top end, it really dies after 6grand.

 

We're leaning toward a custom manifold. The thought of a VI failure or related complications just aren't appealing for the amount of money. We're also very happy w/ the midrange power and the VI would put it all up top w/ our current turbo size.

There's a reason why no factory turbo cars have variable intakes.

 

Not trying to say that you are wrong, but do you know what the best intake design is for a FI car? I mean, a VI would def you help you out a lot, I know it gave me 15ish hp top end on 5psi, and I am running 12 now. I can only imagine what the gains would be now. It just seems wierd how restricting the air and increasing the velocity can make such a huge difference. Its kinda ironic actually, all of us spend so much time and money to try and unrestrict every bottle neck in our cars's plumbing, and restricting gives it more power.

 

I just think the MEVI is too much of a band aid for what we're trying to do. There's no reason the MEVI should cost us 30+ft-lb torque in the low end to give us some hp up top. Improvised control systems and inconsistent operation aren't what we're looking for.

The stock VQ manifold design is terrible for FI but we're not running an extended redline right now which is the only way to get the full advantage of the MEVI so we'll keep power more toward the midrange for now and work on something more ideal.

Shorter runners, larger plenum, and a bigger throttle body will do a good bit more to improve engine flow than an overly complex MEVI.

 

I'd rather spend the time/money to experiment with something and get it right than to go halfway w/ a MEVI. To me, it seems very unreliable. Dropped butterflies, failed RPM switches, etc. I'm always hearing stuff like "I'm not sure if the MEVI opened" or " I had to zip tie it open on the dyno" Even w/ the USIM, my auto is making more power at 7 psi than most turbo 5 spd. cars and there is way more torque. I may pick up some top end w/ a MEVI, but the low end loss isn't worth it to me.

For N/A applications, I say the MEVI is nice w/ extended redline. But for forced induction, there are better ways. We can fab our own manifold using a larger TB, shorter runners, larger runners, and a bigger plenum. A friend of mine and my tuner custom fabs manifolds, so w/ his help, we should be able to work something out. If it doesn't make power on the dyno, we can always tweak it.

 

After getting the new motor in, we finally got to redyno everything at 9psi. Ironically, I pulled the exact same numbers this time. 300whp and 314 ft/lbs of torque. But, power comes on sooner, and the A/F is much better. We tuned it to a solid 10.5/1. Before, it started running lean and I hit 12:1 and higher toward the end w/ the FMU which explained the same power numbers on lower boost.

This brings me to my main question. Is there any way to figure out how much larger wheels affect the numbers? On the old setup, I had standard 300ZX brakes and 19x7.5" wheels w/ 225 tires. This time, I had the 13" Cobra setup, and 19x9" wheels w/ 255 tires. Significantly more rotational weight. I know had I dyno'd again on the old wheel/brake setup, the numbers would look better, not that it matters.

The 660 injectors worked beautifully though, and the car was much easier to tune. All I can say is that if you're boosted, I'd recommend against the FMU and just go w/ larger injectors. My A/F looks so much better, and I feel better about the motor. My old motor went because of ring failure, I'm pretty sure the crappy FMU tune didn't help things.

 

Your auto tranny is gonna die pretty soon with just a vb mod and a cooler

 

With the 00vi, you might gain mid range. You will not lose power with an 00vi.

 

And how do you know that?

It's the original tranny, never been rebuilt. It's not slipping, not acting up in any way. Been turbocharged for 18 months now and it was supercharged for 2 years before that. Just because other people blow up their autos doesn't necessarily mean it won't handle the power.

 

You must have amazing self control. I dont know about you guys but if I had that much power on tap I would utilize it WAY too often

 

damn str8.

 

they tend to from nowhere! i know, i see nrh in your future