During the dyno run on Sunday (the 'other' cleveland owner!) I noticed black smoke coming from the pipes. The amount of smoke grew as the RPMs grew with a nice big puff from the drivers side pipe at about 6000. The drivers side shows less smoke across the entire RPM band.
The car is running great and posted some pretty respectful numbers concidering the mild parts (324HP, 354 torque). The engine has 6000 miles on it and does not generally use
oil. The consumption driving the car back from Arizona was high but I attributed that to a newer engine at the time (3000 miles when the trip began). Now I am begining to wonder if it was what I saw on the dyno. The engine ran at about 3900 RPM for 2000 straight miles.
I thought about the car running rich. But the dyno showed that the engine was actually lean throughout the whole run, 14.0 to 1 or more. With one spot at about 2600 RPM as lean as 17.0 to 1(any ideas on this one, holley 1850s out of the box).
Then I thought about
oil build up in the valve covers being pulled into intake runner by the valve seals. The car does run a lot of vacuum, 16 at idle 22 at cruise.
Then I thought about it sucking
oil into the intake from the lifter gallery. It does have Dexcool in it (but not for long) and I have read the posts about Dexcool and Felpro gaskets.
I thought about rings but I am doubting that very much since the engine is fresh, but I will be running a leak down test on the engine.
The crankcase is ventilated to the atmosphere on both valve covers.
Looking for ideas and similar experience!
Thanks