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Discussion Starter #1
I just fired up my 302 after a short block rebuild and it was smoking more than I like. I used chrome moly rings and hyper pistons instead of cast and have always heard that they take a long time to seal. I've never used moly rings before so I don't know. Could this be why it's smoking?

If that's not it I guess I'll have to pull the heads off and give them a valve job. They only had around 30K miles on them though.
 

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I would give it a while before you get excited.the rings may need a little time to seat.I always use straight 30 wt oil on a fresh rebuild.The heads should be ok with only 30k on them if your worried about valve seals leaking.
Bob
 

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Discussion Starter #3
That makes me feel better. I've only run it for a few minutes; like 15. I'm doing a whole car rebuild on a '79 pacecar and want to get it painted next month. If I have to pull the heads and intake I'll have to hold off on the paint. I wouldn't want to screw up a fresh paint job by dropping a head on it!

I've been slightly concerned about valve train geometry. My heads are DO0E 351 heads shaved .040. They were on a standard flat tappet 302 with fully adjustable valve train, studs and guide plates. Originally I bought hardened pushrods from FMS that were designed for 351 heads on a 302 but the .040 thing worried me as far as guide and seal wear. I had a great deal of oil use in my old engine but I chalked it up to a crappy short block rebuild. It used a quart every 400 miles from the day I installed it and even before I put these heads on it.
 

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I useed a set of molly rings once and have always said, NEVER AGAIN. They never seat. I was constantly changing fouled plugs......some guys like em.......I think they should be against the law.....hope your work bettter than mine.
Good Luck,
LJ
 

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With moly rings it's important that the cylinders are honed for there use. I think a lot of people have trouble with seating because they have there machine work done anticipating cast rings.

I believe moly rings require less lubrication so they work better with a finer cylinder hone.
 

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Discussion Starter #6
I had the machine shop do the short block so I *hope* they knew what they were doing.
 
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