96 Stratus

Did a partial rebuild on my engine: rings, bearings, timing belt, egr valve, intake O2 sensor, head gasket. The intake was full of oil as one of the cylinders blew its rings. I also had to have the cam and crankshaft timing sensors and the pcm replaced. The car runs great but still smokes like a chimney after it gets to operating temp. Could this be partially from the rings not being seated ( it doesn't even have 10 hrs of running on it yet) or could the muffler be full of oil and need to be replaced? There was oil just pouring out of the tail pipe after the motor went initially.