I want to bump up the compression on my 383,built in late 70'(if it matters).I'll assume the worst as far as the pistons being down in the hole,with 346 heads.
Heads have not been off yet,I just need a basic hypothetical here.I'm going to run a copper gasket,and want to mill the heads.Any suggestions to how far I can safely mill them,thoughts of that nature.
Regardless how much compression I do have now,I want to come up at a minimum of 3/4 of a point.

Also any cost effective tips to keep the geometry of the valvetrain correct.
The only money I plan on spending on this motor is for the milling,gasket set and a timing chain after I degree the stock cam.

Thanks for any help guys.Project is coming along nicely thanks to this site and some of the help from guys on here, !