Catastrophic Failure of the Camshaft Bearings

CPMotorworks said

Several good points here-
Tight cam bearings can be a real problem, yet people still force the cam in anyway. Checking the actual clearances is something few people do, but it can save some headaches.
I will say though, I don't buy the "bad cam bearings made it idle rough" idea. Tight and/or lack of oil or debris in oil galleys from not being clean enough is likely culprit of wiped cam bearings.
If you look at the photos of your intake ports, they are rather black from oil and/or reversion, or just a bad tune-up.
Engine problems are never any fun, hope you are able to get it sorted out and back together ok.

Click to expand...

I was also thinking that maybe the machine shop may not have had a bearing properly aligned and then punched it out and reinserted it. That makes it easier to push out the second time/less bearing retention force. Every time a bearing is pressed in or removed, it slightly opens up the bearing hole in the block which reduces the press fit.

You should always check the cam to see how tight it is after it is inserted. If it doesn't spin freely, there may be problems to develop later.

Some bearings, you insert and then are good to go. Others need to be machined after being pressed in. The sb mopar bearings are press in and go.

You should always make sure that the camshaft spins freely after it is inserted. Some people think a tight one will "wear in".... NOT.