The solution is probably to go for a modern flattop at zero deck Run the god old 0.039" thick headgasket and then cut the heads until your chambers are small enough to get the desired compressison.
But that depends on what heads you have and if they can be cut far enough to make that happen without getting into other isues.
If your problem is the 0.040 overbore,then i think i have seen forged Mahle flattops for that boresize.
Thats what im looking at doing with my .030 over 340 to get similar compression while avoiding to use those heavy old pistons,but im also stuck with the open chamber edelbrock 340 heads.
