looking at a set of performer rpm 6055 heads and also considering 115 cc chambered chinesium. (they say they are australian, but...) they have the vortec-ish heart shape chambers. does that point between the valves come too close to the piston dome? it doesn't seem near as huge as the iron L29 head chamber.

best I can say is,buy them,put them on w/ some clay and see if it works.If not,,grind the chamber to work w/ the pistons.

the edelbrock 6055 head comes with a 118 cc combustion chaimber and is pretty much a aluminum version of a gm rect port head.it is a good choice for a replacement head but won,t flow anything near what a dart or afr head will.i have no info on the chinese heads and i won,t use them.