in2twins

I have a to4 with a .60 cover, and a .81 p trim hot side. Will going to a .96 hot side help me to make more power, or simply move my powerband up. I am currently making +/- 350rwhp@20 psi. Can I get to 400rwhp with this turbo? Opinions....

1FastT2

iTrader: (1)

It will free up more HP while it moves your powerband up in the RPMs. You should be making more then 350hp at 20psi so something else might not be setup on your car properly, perhaps tuning. Im running about 380 to the wheels right now with conservative(rich) tuning @ 14psi and an 0.84 hot side.

in2twins

My afr is 10:1 from 3000-6500, and my timing is conservative as well. My traps at the drags were in the 112s when I was at 15 psi, I since turned up the boost to 20psi. I can't seem to find an O2 sensor for my DIY wideband, so the tuning will have to wait.

12aTurbo510

I had a .81 q-trim and made 390 to the wheels at 21lps with a 12a tuned to 11.8. Sounds like you might have another restriction in your system. Putting a larger exhaust housing on a turbo does not make more horsepower unless it is a restriction. Your HP is primarily dependent on your compressor wheel. Which wheel do you have?

Badog

It's an equation, guys. It revolves around the amount air (with fuel) you can push in and get out. Not to mention light off properly. You have many potential limits within that. Matching the turbo to your porting is key. Slapping a huge turbo on a stock port engine isn't going to 'guarntee' huge numbers. The tuning brings it all out into the light.

Carl Byck

my set up is a steet ported 13bt/rew(rew housings, and rotors)
plenty of fuel(720/1600),sxfpr,big lines,etc
E6K
3.5" full exhaust
plenty of spark(3-msd6a), 10mm wires, ngk race plugs, etc
and everything...
A Q trim will flow a shitload more than a P.
I'm looking for 450-500rwhp, a .60/.81 p trim will never do that.
I am tuned conservatively, my tuner feels he can get 400 out of my current set up. If I understand this thing, then a bigger ar will move the power band up, if I am moving more air at higher rpms (than low) I should make more power w/a bigger ar. As to O, P, Q, H, R, trims they flow, and spool differently, and therfore have different HP potential given everything else to support the turbo. Where I was headed was for a TO4 with a .60 front cover many guys are using a 1.00 ar of various trims, I am using a .81 p trim. this is a relatively low flowing wheel compared to a Q trim. What gains might I expect from a .96 p trim? All this is probably mute at this point as I am going to use a larger turbo after deciding that the gains to be had with the bigger ar are minimal.
All said, I think I will go with a 67mm q trim turbo with a .96ar Thanks for everyones help, Carl

turbogarrett

iTrader: (1)

is a q trim t04 a good choice for a street turbo? i have asked around, but never gotten any helpful answers. anbody have cfm #'s on a p vs. q trims? anybody drive a q trim streetcar?