349 CI on the cheap
My concern is more for the compression height. Adding that .135" in most blocks means popping out, like what you mentioned. I know you can take some off cast or forged pistons, but milling the entire top of a Hyper puts those rings even higher. 70, my feelings about the strength of the crank turned way down, and the cast pistons makes me set that limit. I tend to be conservative in that type of thing because it suits me better. Plus, in reality, most guys are not racing the engines much higher than that unless they know little about torque peaks or run 4.30 or lower gearing..lol..
BJR, do you know any shorter (compressionj heights in the 1.65 range) 318 part numbers? I cant find much. But there has to be somkething. Maybe a marine or agricultural piston number...