looking at that page " a" is the valve seat angle of 45. is the next fiq represent the back cut? also there no mention of stem undercut to the valve? i wonder if it possible to get better flow with 30. backcut and .035 undercut to stem? only way to find out i suppose is to experiment! carn,t wait to get my hand dirty after 2 years ownership i still haven,t even touched the engine it been that reliable 8)
zia