I've calculated that I'm going to need about 1 bar to get 400hp in race trim using VPC16 or something similar along with a test pipe. 400hp will be pushing the limits of the stock parts, but I'm not going to be running around with that much boost just to get from point a to point b.
In street trim I will be using a cat and pump gas and probably 7-10 psi which should net about 325-350hp. This should do nicely with a good amount of torque when compared to the N/A 3L.
I don't think there was anything wrong with that Siboney SVT power curve, I just think that he started the dyno at a late rpm. I've seen that dozens of times for cars that just don't make power in the lower rpms, they do that so it wont take up alot of dyno time. Not even the soggiest T4 would do that unless he is having tuning issues and even if he had tuning issues it would have probably shown up in the dyno.
Originally posted by Rara:
for 400hp I'm guessing somwhere along the lines of 15psi, and fwiw, I believe you will definately need forged rods for that power level.
If you truly are gonna run in the neighborhood of 15-20 psi I think that turbo is ok, but anyhting less would demand a smaller turbo, or you will end up with a power curve like the last turbo 'tour that was posted.
Good luck, and let me know if I can lend a hand in any way.
