hey guys, i have a 98 cobra(with only 40000KM) with a p-1sc procharger that have a 3.60 pulley gives me around9psi on my gauge, and the beast is equipped with long tub headers and xpipe with cats and a side exhaust pipes and some other bolts on with the stock engine. My questions is i would want to run more boost is a 3.40 good idea, and my gears are 3.73 would it be better to have 4.30. And some people tell me that my side exhaust makes me slower or loose some good power is that true? in the next week am going to tune it with a tuner on the street not on the dyno is that enough to have it "will tuned". Guys how much power you thing am making??? Thanks guys & will appreciate you help!

 

A 3.4 pulley is going to put you around 11 lbs of boost. You do NOT want to tune this yourself. It needs to be put on a dyno to make sure the a/f is right. The 3.73s are good. No since in going with anything else. I've been told the side exhaust is very restrictive as well.

 

ok, but is 11psi is safe to to a stock engine? or what is the max that i can go?