[Febo]

Im with black rose, pull your mani at least and check for oil or burnt up oil up in the exhaust ports of the head. If its just really sooty but not oil soaked like it sounds like it should be chances are its not in the engine. For there to be actual oil in your exauhst system I would think you would of noticed a huge performance loss due to plug fouling for it to run thru the cylinders and then out your exausht in that way. Probably turbo seals.