My friend just had forged pistons and new bearings put in his LT1. Its been about 500 miles and now his car surges at idle badly, sees slightly lower oil pressure, and sometimes stalls. Its either bad gas or a bearing he figures.

He's draining his tank tonight but I was wondering if you could tell by looking at the bearings with the oil pan off if one of them had spun? There is no tapping or rattling noises coming from the motor.

Would we be able to simply drop the oil pan, swap out the bearing, and seal it back up?

Do you have to remove the timing cover to remove the oil pan?

 

You can redo the rod bearings with the engine in the car and dropping the k member with something holding the engine up and no you do not have to remove the timing cover or rear main. however, idle surging, running like crap, not knocking sounds like something else than bearings.... gas is a good possibility though.

 

My guess would be Shell gas but he has his doubts. He has used Mohawk 94 octane all his life and then he filled up with 91 octane Shell and it started surging shortly after.

 

If you spun a bearing it would be quite obvious and loud. The low oil pressure could be a number of things. Bad sensor, wrong oil, poor tolerances etc..