why is my thumb moving on its own - SPORTS
Roll oversteer feels twitchy. There are lots of "rules of thumb" about what should be parallel or pointing up or down. Mostly it's all bunk.
Context Explanation
Just do the calculations and design a geometry for the handling characteristics you want. Some adjustability is always a good thing as well. a good rule of thumb is, whatever you can add going from 1.5 to 1.65 rockers, i.e. around 10% more lift, you can generally grind into the cam itself for hydro flat tappet.
Image Collection
Insight Material
then if you run the same 1.65 rockers, you can add that much more again with rocker ratio. so...in case of a Pontiac V8, a .470" lift cam can become a .510" lift cam, then ...