273 commando Build

UPDATE UPDATE UPDATE !

SAD NEWS AGAIN ! Blew another head gasket again .. same pass side , different location now on #8 and blew into the valley again . this last build i installed arp bolts torqued to there spec #100 .with there lube , chased all the threads agin blew out the bolt holes, head were milled straight, .003 off head and retorqued after a few heat cycles.
I have noticed where the gasket blows is where it hasn't enough material clamping surface on the gasket between the bore and the edge of the valley approx 3/8/-1/2" width.. because the head gasket has such a big bore . I used 318 head gasket on this build. still too big for the stock 273 bore... the 273 has 150 psi when doing compression check .

this last build was impressive ! reason being the engine screamed with endless power.. eveerytime the engine blew a head gasket was when pushed the gas pedal down just enough to open the secondaries 3/4 way .
this engine revved like it was on nitrous .. It was that fast of a rev. no BS !
stock 920 heads with just alittle clean up on casting ports that's it. isky cam .. If you need more info just look back at previous posts here.
the the question now is what should I do.. o ring the heads stud it ? up for suggestions maybe that block is warped or the bolt holes are all pulled up stretched upward now after the 3 times of messing with this issue..
I'm tired of messing with this same issue all the time .