I just now found this from jalopyjournal.com talking about a "F@rd":

New hyd. and solid lifters have a 96 inch spherical radius ground on them and the cam lobe has approx. 0.002" taper so that it contacts the lifter off center and spins the lifter.
Proper operation means that the lobe and lifter don't rub but roll together at the same surface speed.

Last edited by buoymaker; 05/21/2022 7:22 PM.
"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."