Hi I just installed new valve covers on my 351. After I started up the engine it starts to smoke closer to the back. I think the only thing that would cause it, is pieces of old cork gaskets got into the oil after scraping them off. It smells alot like something is burning and looks like it is coming up from the transmission area or close to where the headers flanges meet the exhaust. if anyone knows what would cause it. the smoke is white if that can help identify it.