Originally Posted by y2k600f4
Purchased in car with about 50-100 miles on it that had a freshly professionally rebuilt 383. I drove it home 300 miles, dumped oil put new filter and quaker state 10W30 (3/08). I drove it approx 200 miles in the last 6 months (busy fixing little things); and it is burning oil some oil. Pulled a plug, it is black and wet and I get lots of gray smoke with black specks all over my bumper and garage floor; lots of black soot in tailpipes. Oil was low when changed recently, put in again quaker state 10W30. I figured the rings were not seated yet, but after talking to others they informed me they should of seated already….I thought somebody could give me some insight on this board. I have not began to trouble shoot (compression test, leak down test etc); I don’t have the tools but I am willing to get them. Any help would greatly be appreciated. The following is what I know about the engine build.
All new parts which include the following (this is all I know)
Summit Cam sum-1106
Chrom moly +100 push rods
Holley 4160 750 Carb
Procomp Aluminum Heads 190cc/64cc
Performance products 52026 crosswind intake
New Eagle bottom end; externally balanced (.040 overbore, Flat top +5cc pistons)
Felpro 1003 head gaskets
Felpro 1205 intake gasket
Depends a lot on the rings and if the wall honing and ring materail were matched.
Chrome rings if used need a coarse hone and still can take a few thousand miles to seat. If they were missmatched with a smooth hone used for moly rings they may never mate.
Moly rings if used need a smoother hone finish but usually break in and seat quickly. But if matched with the coarse hone wall for a chrome ring, very often the moly coat is "sanded" off and the rings will forever push oil into the combustion chamber.
Life just isn't as simple as in 1960 from a ring materail and cylinder wall finish standpoint. But, also, only driving 200 miles in 6 months isn't exactly the kind of use that seats rings of any sort. Molys on a smooth wall will do it, but for chrome you've got to get a bunch of heating and cooling cycles and maybe even a little wailing on it a few times to drive 'em home. Plus that little use isn't good when trying to break in a flat tappet cam. If you've lost a lobe and lifter you will also have oily problems on the plugs and in the exhaust.