360 Main bearings

[High5]

Hey engine guru's, Got a question.

I have a 360 I have been tearing down and now have a question about the condition of the mains. The two I measured, measure .003 with plastigage. Should I replace them now, or is that adequate??? What about the rod bearings??? Should I replace them at this point as well??? Trying to drop this in on the cheap, but the cost keeps creeping up. I have a practically new timing cover and oil pump gears on the way as well as an Edelbrock intake. I plan on going with the Summit 8600 cam.

I'm pretty new to V8 AMC's so any advice will be appreciated.

The engine has around 80,000 on it.

Thanks
High5

[Goose]

I know you want to get by on the cheap, but dude .. replace the bearings.. save the headaches.. They are cheap compared to the result.. I would replace rings, bearings, and gaskets as well as the oil pump kit. It's cheap insurance. and at 80,000 it probably is time.

[ironman_gq]

They have been having lots of problems from what I understand with the summit 8600 cams. some people have gotten them with poor machining and/or improper heat treating they fail almost instantly. Tell everyone what you want to do with the engine and see if there is a better cam for the job. I would do it right the first time and save money in the long run. Good luck with the build!!

[82Waggy]

.003 main bearing clearance is within spec. Replace with std bearing size. If you polish the crank, you may want to go .001 oversize. IF the crank is grooved, have it checked and reground as necessary - use the applicable oversize bearing (.010, .020, etc).

[High5]

The crank itself looks really good. No grooving or anything. Do you think that just doing bearings would be sufficient there??? I suppose I need to do some measuring on the block to see if boring is necessary. I just got my new timing cover, intake, and valve covers in the mail. Well, they aren't new. They are slightly used. The timing cover looks great in comparison to my old one. Intake is dirty, but intact. Plus, it's a ton lighter than the stock one. I already have a set of 502 heads to go on as well.

I sure don't want to bore if I don't have to. Suppose I need to find a cheap bore gauge and find out.

High5

[82Waggy]

Crank journals, cylinder bores, and the crank end of the connecting rods go out of round.