My 83 sc targa duck tail would not open , Worked on it for some time got it opened and adjusted . Took the p car out for a spin this after noon,heard a knocking sound ,then I could no longer see the traffic behind me , (white smoke every where coming out from the exhaust) Looks like maybe new motor. If so should I rebuild the 3 litre or go bigger? Hope the rest of the week goes better.