I could really use some expert analysis here as I tackle my motor problem.
Quick Review: 418 SB, AFR 205, big lumpy cam, Mass-Flo injected, dyno 560ish on pump gas. Professionally built with all the right parts. Motor starts, runs and pulls perfectly. Runs cool and
oil pressure is great all the way across.
Oil consumption is excessive at a quart every 200-300 miles. No leaks. No start up smoke, no smoke at cruise, no smoke at closed throttle, wispy smoke from passenger side pipes only at shut down, smells "funny" like wax burning. Compression was a solid 200-205 all cylinders, dry cranked.
Key Point: Plugs look perfect, EXCEPT the two middle cylinders on the passenger side....they are fuzzy black after only a short run.
My plan was to replace the intake gasket first and I have a top of the line SCE to put in there. If that didn't solve it, then on to the valve stem seals. If that doesn't do it, then I would move to the rings.
NEW INFORMATION: I really hope someone can diagnose and either confirm or lead me in a new direction. The motor has a low speed ping or clatter on the passenger side, when you first come on the throttle, off of idle. I get a familiar clatter that sounds like it is only the two suspect middle cylinders and a LOT of blue smoke at that time. It clears up after a second or two and the exhaust runs clear after that, for the most part. On hard acceleration in second from 2,500 or so, no smoke at all and runs great. Turn it off and I get that wispy smoke that smells like wax burning out of the right side pipe (every time). It doesn't clatter every time.....clatter, lots of smoke, no clatter no smoke. I just running it enough to try to determine what to do next.
Can
oil being sucked into the cylinder via an intake gasket leak cause the pre-ignition? Can that be the source of the smoke and not the rings? Maybe to much air as well causing the ping?
I know the rattling or pinging is rocking the piston or pistons skirts around on that side of the motor and I suppose that might make a broken ring or rings oil control situation worse. I just don't understand how rings would be considered the prime suspect with only two of the cylinders, next to each other on one side of the motor, look to be the first line problem (fouled black plugs there only).
I'm ready to start pulling things apart but if I really need to just go deep into the motor I had rather do it up front and not one step at a time, all of which will need a do over if I have to look at the rings. On the other hand if it's a simple leak at the intake sucking oil, that's certainly where I would like to start.
I guess my main question is can sucking oil through an intake gasket leak cause the pre-ignition. If so, I think the smoke at that time is coming from the intake leak. I just don't feel comfortable that I understand it well enough yet.
Man, any help here from some experience or expertise would be greatly appreciated.
Hybrid Mode
