All of the heads interchange. the 400 heads have some extra steam ports drille din them but that only matters if your putting them on a 400. You can use 400 heads on other small blocks with no problem. IIRC 305 heads are higher compression if you put them on a 350 but do not flow very well so its not really worth it.Jonx4x4 said:Thats kinda what I was figuring. I dont think the size of camshaft bearings ever changed, and I think the only other small block I couldnt interchange heads with would be a 400 small block, because I hear they have like 4 extra head bolts.
I dunno. I guess Ill just have to find out.