dirty_old_chevy

Is the combustion chamber diameter on the 243 heads larger than the cylinder bore of a 5.3? If so, I would definately get 5.7 gaskets, so you dont run the risk of the head gasket hanging out into your combustion chamber. Or just get L33 gaskets, since they came with 243/799s from factory.

devink

iTrader: (2)

No they are 5.3 heads (862 castings)

dirty_old_chevy

oops, I dont know what made me think that, lol. I would run 5.3 gaskets, but if they had combustion chamber work to unshroud the valves, it still wouldnt hurt to measure the combustion chamber diameter.

devink

iTrader: (2)

Thanks for the tip. They did clean up the chambers and the valves are 2.02/1.6 so it would be a good idea to measure.

GMCtrk

iTrader: (27)

I'd use ls9 head gaskets. $90.

grey matter 04

iTrader: (9)

Doubt he does that!
He's unsure of using ls1/6 gaskets with a bore size of 3.910 vs a ls9 gasket bore of 4.100

devink

iTrader: (2)

So it doesn't matter if the ls9 has a larger bore? This is what I'm confused about.

craigsix

small block chevy 350 gaskets arent 4.00 bore they are larger and people have been using them without problems.