those 8553pt gaskets are .045 compressed and run.
I ran 165-170psi cranking ' 9.9 static' with those head gaskets and had no issues.
I used 91 octane, quench domes w/open chamber heads around .037 q/d and 24* initial & 32* total timing.
140psi is weak, but the cam is bleedin it too..., so doesnt mean it cant detonate up top...but just maybe the tune was crap.
