[Formulas]

the main point of my comment was roller size change on the same roller lobe effect on duration it could be very little as .700 to .750 isnt that drastic of a roller change iam not thinking duration would change much either

in theory as its obvious you couldnt actually do this in a pontiac if you changed the roller size to 1 inch it would be rolling up the ramp earlier and or faster in the cams rotation and that translates to duration


to possibly understand what iam saying take it to the extremes a roller lobe under a razor blade the ramp has to travel further to get under the blade to lift it conversely put a roller lobe under something as big as a tire the tire would be elevated a longer amount if degree lobe rotation

thus a change in roller diameter has to effect duration of tappet lift catagorically

i never said it would be earth shaking game changing from .700 to .750