I ran my car out in high gear this evening at high boost. It was 28 to 30psi+. Not sure exactly, because it was HAULING A$$ and I was afraid to look at the guage. But anyway, the headgasket got pushed out, I know at least in cylinder #4 because I can see it sticking out from under the head. The plugs look fine other than #4 being wet, with no signs of detonation on them. No oil blew out anywhere, and the dip stick was still in place. I was able to limp it the 1/8th mile or so back to the house. Is a Cometic gasket going to be better for high boost and high cylinder pressures? What are some of the reasons other than just shear pressure to cause a head gasket to completely blow out, (timing,detonation,head lifting, needs coolant mod to #4 etc.?). If I can get a few more bugs worked out this thing is gonna fly. I nailed the throttle from around 50mph in 3rd gear (high), and in less than an 1/8th mile on my test strip I was doing well over 100mph! I know one thing, when I pull the head, the waste gate will become external. The internal gate is useless. I had straight manifold pressure going to the wastegate no bleeds or anything, and it still will boost that high!