In respect to valves, In the OHV world my understanding id 90% or the bore diameter should be total valve diameter and of that number 60% should be intake and 40% on the exhaust does that hold true on flathead engines or is one better than the other? so 3.500 bore means total valve diameter of 2.84 (intake and exhaust diameter added together) so 1.7 for the intake valve and 1.14 on the exhaust?
