blower with gt40ps

gt40p's raise compression, just FYI if you have a stock shortblock and plan on alot of boost.

Use a thick(er) headgasket and most, if not all, of that compression gained will be lost. Even if you use a very thin headgasket, you won't have any problems.

I personally would sell those heads and pay a couple hundred more and buy aluminum. People pay some nice coin for P-head that's been ported with bigger valves. It's up to you. It'll still run good either way.

Joe