motor im putting together is a 340 .040 4"crank,pump gas roughly 500hp,ive always used cloyes in the past,but was looking at progear timing chain set,what is the better set-up a 3 keyway or a 7 keyway,i see the keyways are in the cam gear on the progear,cam is a herbert solid roller 108* lobe seperation, i will be installing it at 104* do the multi keyways help for timing advancing or retarding or will i still have to use offset keys also thanks mike