OK, so rocker arm ratio it is!

Well, the closer the pushrod pivot is to the continuation of the rocker arm's nose centerline (as it cuts through the center of the rocker body and exits through the oppossing end), the higher the rocker arm ratio you end up with. The rationalle there being the distance from the rocker arm pivot center is shorter and subsequently that produces a more direct and therefore larger movement at the rocker arm nose. The further away from that ideal straight line you get, the longer the distance from that pivot point to the rocker arm pivot itself, and therefore the lower the rocker arm ratio.

I played around with this on my 1.6 design ratio W2 Harland Sharp rocker arm setup for a different reason (explained below). Specifically I measured the difference between setting up the adjuster to show just 1 thread below rocker arm body vs 3 threads, so a difference of just 0.100" on a 20-TPI adjuster.

The resulting ratio average over the full lift of the lobe (so comparing the actual valve movement vs lobe lift) netted me the following results:

1) 1 thread => avg ratio = 1.550
- the geometry uncorrected ratio was actually 1.593

2) 3 threads => avg ratio = 1.526
- the geometry uncorrected ratio was actually 1.619

...the result was NOT significant enough to lose sleep over, however it spelled out the lift difference I was looking for, that being an avg lift loss of about 0.011" on #1 and 0.019" on #2.

Now the reason for this: I ordered the B3 geometry correction kit and knew ahead of time that the resulting valve lift would be smaller due to the correction of the rocker arm movement itself (all in the name of improved valvetrain stability).

So from my perspective: is the benefit worth the potential machinig cost (to clearance the rocker arm) and the potential weakening of the rocker arm body itself?