Compression questions

[hohner0006]

Last year I put 343 pistons in my 360 to boost compression. I'm running 58cc heads which I figure gives me between 10.5-1 or 11-1 compression. If I step up to 51cc heads will i get 12.5-1 compression? If it does, are there any issues concerning head gasket failure that I need to be aware of? This is a race-only engine so I'm going for max power without totally rebuilding a whole new engine. (I'd like to use what I already have) Thanks!

[jeepsr4ever]

You should be safe with most head gaskets. When we go over 12-1 compression we tighten all bolts 10 extra foot lbs. The fel-pro, ROL or copper gasket should work great for your application

[hohner0006]

Thanks for the info......I had read somewhere that high compression AMC engines were hard on the gaskets. I'm going into new territory with this engine build so I want to make sure I know as many facts as possible to avoid any mistakes. Any suggestions for a custom header builder? I'll need some headers built for high rpm power.

[tufcj]

You'd have to truly calculate it out, but the 291C heads (51cc) should only raise compression between .5 and .75. Even if you're at 11:1, you should stay below a 12:1 ratio.

Bob
tufcj

[fuzz401]

just throw flat tops in with a 0 deck height and the 58cc heads you will be at 12.5:1