I'm planning on replacing the lifters in the 302. I'm leaving the cam but after the new lifters are in do I need to go through the cam break-in again for the lifters. I'm installing roller rockers at the same time and was just wondering if there is a special break-in for just the lifters?
Since the surface of the flat tappets are machined slightly rough so they can break in to the specific lobe they run on, I would treat it the same as you would a new camshaft. (Don't let it run at idle for at least 20 minutes) Idling inflicts the highest pressure on the lifter and lobe surfaces.