im gonna switch cams, and i know you are supposed to be able to rotate the ex. cam to push the lifters up into the plastic holders, but if the new cam has a higher lift, or base circle, are the lifters going to be far enough up for the new cam to clear? i remember when i built the engine, the lifters felt tight enough to stay up (i hope) in the retainers-thanks

 

I think that's why u have to spin it hard and fast.

 

The lobe can't be bigger than the journals for the bearings so if they clear coming out it will clear going in. Rotate the new cam slowly as it goes in it will go. Last one I did I had a problem with one lifter not high enough. I actually gently used the cam to nudge it higher.

 

I always shove a peice of tubing into the holes just in case, don't need to be yanking heads on simple cam swap.