When I hear myself saying it in my head, it’s seems pretty obvious....... to me at least.
You wouldn’t install a new crankshaft without measuring the journal sizes...... would you?
And if you didn’t...... well you could still plastigauge it.
Of course, plastigauge isn’t an option for a full round bearing..... so at a minimum you’d want to at least measure the journals and make sure they’re to size.
Same goes for straightness. I always check it...... on cranks and cams.
Factory BB Mopar blocks are fairly notorious for having screwed up cam tunnels........ so when a cam won’t go in, it’s 50/50 which is the culprit. If the cam is straight and to size..... the problem is the block.
In cases where one cam fits where another doesn’t....... its a safe bet the problem is the new cam.
But..... you gotta measure it to know for sure.
Probably the best analogy that could be be made - crank versus cam - measure them both.
Up until I stopped visiting the engine plants at Chrysler in the early 2001 time frame, we machined ALL the cam bearings after they were pressed in to the block.
They were called “green” bearings because they were unfinished.
We did this at the trans plant too on ALL the bushings in the auto transmissions.
