whats up everyone.....im trying to slowly ressurrect an old 1966 chevelle malibu with a straight six. I've managed to get the thing going and stopping on its own. the next thing id like to do is get a tach setup. In the meantime i've got blue smoke coming out of the tailpipe after 3-4 minutes of warm up. could anyone tell me what this is and where to start in terms of fixing it?