Bastard 20G?

[scheides]

Headgaskets get blown by detonation and high boost pressure. a 60-trim will be fine on your stock motor, just do not run more than ~25 lbs of boost. Past that, the stock head studs are not strong enough and the head will start lifting away from the block. Add in the higher likelyhood of detonation at those high boost levels and you got yourself a wicked detonation. Go for a scm61 or something, and tune it for like 19-21 psi and you'll have yourself a pump gas monster.