RWagner

running on stock internals, how high should I set the boost before I put in a new headgasket? I've heard 6-7psi.

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Turbo's are neat

 

schwett

6-7psi is the max, even at 6-7psi there is a reasonable chance you will blow your motor.

a standalone computer, big injectors, a j&s, and good tuning seem to minimize the chances of this.

RWagner

what will the result be if I swap out my headgasket to lower the compression?

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Turbo's are neat

schwett

if that keeps detonation at bay, it will certainly help. however, it does nothing to increase the strength of the pistons themselves, and the forces exerted on them are going to be approximately the same in a 9.0:1 300whp motor as a 10.0:1 300whp motor. given that some people have lost their pistons without any ongoing audible detonation, it MIGHT be that the pistons just can't take boost pressure, period. detonation will surely kill them in a hurry, and the reduced compression will help you keep detonation away. i still think eventually you'll lose your motor at anything more than 6 or 7 psi.

but that's just my $.02, based on my scant experience and the couple dozen users i've been keeping an eye on here and on h-t.