Rauq

iTrader: (1)

I'm tearing down an LM7 for a turbo build, and I've got it down to nearly a bare block now. 120k on the motor, and it came from a Tahoe, so I would guess it was babied its whole life. All the main journal bearings and rod bearings are spotless, but the cam bearings are smoother on the bottom (crank) side than the top (intake manifold) side. I wouldn't think this is surprising, given that the camshaft will spend its life being pulled towards the crank, and the oil passages are located on the side of the bearing.

Question is, is this surprising enough that the camshaft bearings should be replaced? The cam came out as clean as the LS1 cam I pulled from my GTO, although I did that one as a regular cam swap so I didn't get to see the camshaft bearings. The LS1 cam is going into the 5.3.

Snkebait95

iTrader: (16)

Pics?

Rauq

iTrader: (1)

I can get them this afternoon, but generally it's just that the bottom half of the bearing is smooth and the top half isn't, like it's been stained with oil and hasn't been worn down at all.

AES Racing

iTrader: (6)

Take a look at these bumpsticks:

http://store.aesracing.net/camshafts/

mark21742

Have anything bigger....like in the 26x-27x intake and 27x-28x exhaust around .630 lift and 115-116 lsa for us guys that want to spin well breathing 400+ci motors up past 8,000?

mark21742

Rauq, most of the time you will have more wear on the bottom side of cam bearing than on the top side of...it is pretty common to see some copper and the top look almost untouched.

Rauq

iTrader: (1)

Thanks but no thanks... I already have an LS1 cam sitting here, and I'm not looking to spend nearly as much on a cam as I have in the entire engine plus a set of heads so far.


That's what I was looking for, thanks. I'm going for max benefit/min cost here.

chrisfrost

iTrader: (8)

Don't waste You're time withan LS1 cam ,,,,,,,,,at the very least put in an LS6 cam or You can pick up an LS2 cam for around $50 and a newer timing cover from Ruperts used auto parts in Ok for $50 shipped ,,,,,or a Hot Cam or an ASA cam .

Rauq

iTrader: (1)

I'm not wasting any time. I have the cam here and it's free and it's slightly bigger than the stock LM7 cam. If I said hey $50 here and hey $50 there I wouldn't be able to get the whole thing together. There will be a lot of cheap hp upgrades down the road, though. Since it's just a project car, I don't have a problem with taking it down for a week to swap in a hot cam or LS6 cam down the road if I decide I want 30-40+ hp.