K, i do have a question and this is just a question not an attack.... a 318 is pistons and a crank, if you put on good heads/cam/springs that's the same as you do on any motor to spin rpm, what is holding a 318 back from high rpm compared to a 340 if cam/heads/springs are equal?
Bore size will have an effect, on 2.02" or small valves probably not gonna make huge difference especially at the power levels (cfms) most are trying to get out of a 318 250-400 hp