whats a good set of heads
I've just built a 318 with 915 "J" heads
I had 2.02/1.6 Ferrea 5000 valves installed
I cc'd the combustion chambers to compare the standard 318 heads to the J heads before and after the bigger valves were installed.
1973 318 heads 1.78/1.5 valves 66.5cc
915 J heads with 1.88/1.6 valves = 70cc
915 J heads with 2.02/1.6 valves = 66.5cc
Deck has been surface ground, but no more height has been removed than is necessary.
I used KB399+0.030" dome top pistons which require no notching of the bores whatsoever.
Cam is a hydraulic Comp Thumpr. Piston to valve clearance is approx .180" (lots!!)
CR is calculated at 10.39:1
engine should be capable of 350 hp with the right intake and exhaust.
port work and a more aggressive camshaft should push a similar combo to 400hp in my opinion.
Hope Some of this information is relevant and useful. Frosty.