Quote: Also, is absolute geometry really needed, for most purposes Im going to assume the rocker manufactures have it really close to begin with.
Really ?!?! You were sounding pretty smart for a while there but you've just dispelled that notion.
I hear you, but Im referring to the word "Absolute" Im sure many of us dont have it with our rocker arm/shaft/valve combos.
Like everything else in our hobby, there is rarely an absolute right way. It usually involves a trade-off of some kind. In this case, the trade-off seems to involve centering the roller on the valve tip, which often does not lead to "perfect" valve train geometry. Due to the smaller contact patch with roller tip rockers ( verses scrub type rockers ), I personally am willing to sacrifice "some" geometry to be able to get the largest roller tip contact patch ( middle of valve stem). This also helps in the valve stem wear dept. On the down side I am probably sacrificing some area under the curve.
