These tappets will run in cast iron or aluminum tappet blocks Recommend fitting the tappets to the blocks with a clearance of .0007" to .0012" Produced from billet bearing steel A true center-line for roller life and exact cam timing State of the art pushrod seat, machined with the same segmented parabolic cup as the JIMS« roller rockers Hand fit hydraulic unit to a running fit of .0002", with ultra precision air gauging system. P-G TAPPET +002 53-84 BT
