I have what I'm pretty sure is a T04E with a T4 turbine housing with a .96 A/R
I wanted to run about 10-12psi but was told that is a little too much for this turbo. I am currently running 7psi and just dyno'd it at 347.2hp and 356.9tq at 3200ft elevation and mods in my sig. What do you think my gains would be if I upgraded to the GT67 and a smaller .68A/R? Would that be capable of doing what I want? (450-500 at the wheels)

Thanks

 

I'm running the 60-1 on a front mount at 10 psi. I looked at the compressor map at one time and did notice that I was out of the efficiency range, but it works. :-) I honestly don't think its really worth upgrading the turbo for the extra 3 psi.... Every other person will say that its just generating heat, (it's true, to an extent) but they just like to spend money.

I'll probably push it to 12psi if I ever get some meth. I'm out of fuel.

 

What size injectors are you running?

 

8.1 Marines. 42 lb/hr I believe.

 

and your pretty close to sea level with my 44# injectors at my elevation I should be able to run 12#s

 

IMO the ar is too small...

 

i had the 60-1 lq4/t56. i upgraded to the gt67 ar .81 and i can tell you theres a noticeable difference and im running 10 psi w/meth.

 

If you are going to upgrade, I would suggest something along the lines of a Masterpower S70 or even a T76 with a .68 A/R. I started off with the T60 and ran 10psi with the same results you got. I recently upgraded to a T76 and at 10psi it feels much stronger (I run 14+ psi). Boost is instant. I have to feather the throttle to keep it from spinning. It will definitely be able to support you power level goals as long as you have the supporting mods to go with it.

 

More instant than with a smaller turbo? Intrest piqued. Please explain.

 

Yep, I was running a T-60 with .81 A/R on a 5.3. It spooled pretty quick but when you go to a smaller A/R such as the .68, it makes a huge difference. I ran a MP S70 with the .68 on the 5.3 and it seemed like I was always in boost because of how fast it spooled. Add more cubes after I bored the 5.3 to a 5.7(with 317 heads) and like I said, instantly! Even the T76/.68 boosts to 14+psi in a blink.

The compressor side of the turbo isn't what determines how fast it spools. It's all about the exhaust side and the volume of air that is turning the turbine. That's why wrapping the exhaust is so effective to keep the air hotter which will have more volume.