Agreed! But, for example, if you are starting with a 318, and stroke it to 390, I think I would upgrade from a 318 head. Eddie's would be a huge improvement, and for a street strip car.... trick flows.
Street strip? Trickflows? A 318?
Assuming the bottom end is built near 11.1 compression and cam'd .550+ . That's 190cc 4.040" or so chamber on that LITTLE [email protected] bore.
Better relief the bores a bit.
As for 390 cid or heads...
If the 318 heads are capable of what folks claim when ported.. then they'll make for more useable tq than the 318 with just eddy heads. Best head, nope. But if I had the choice..and had to pick.. I'll pick the extra cid and work the small heads over myself. Lift the valve .500-.550 and turn up the duration into the 300's