hi all . ever since i have had my cylinder overhauled my car puffs blue smoke on overrun and after it has been idling for a while . it did not do it before and the head gasket was not gone ., i just did it as a matter of course as i am fussy . the car has done 46000 miles and i change the oil every 1000 miles using motul 300v 15 50.. the only thing i have changed when rebuilding is i have fitted arp head bolts and fitted a bailey tubo feed pipe and filter . as i am a mechanic smoking in this way is usally to do with valve seals . but i have been back to engineers who did the head and they said they had no problems. what i did notice when the head was being done i noticed all the valves were just put in a tin so i dont think they were put back in there original places , which too me is bad practice . as you can guess i am not very happy about this and dont really want too remove the head again but it dont look good smoking like this and it needs to be repaired . could the turbo suddenley have started to leak oil or could it be the feed pipe ... any other ideas kind regards mark freestone