Compression ratio

[Brian Hood]

Hey everyone! I have a super low mile 1971 318 engine. I am considering using a larger cam with between 450 and 500 lift. How do I raise the compression ratio to higher number? Do I use bigger pistons? Should I have the heads milled down? Does anyone know what the compression ratio is for a stock 1971 318?
Brian

 

[toolmanmike]

Brian, 8.6:1
http://www.valiant.org/valiant/engines.html
I would suggest you check yours to get an actual number before milling and machining. Yours is probably closer to 8:1. I am rebuilding my 273 and used 10.5 pistons and milled my heads .030 and with new valves, valve job and thicker head gaskets, I ended up with 9.6:1. toolman
http://www.forabodiesonly.com/mopar/showthread.php?p=909438#post909438