Trouble shoot blue smoke

[John 550]

A friends car with a 428 has just developed a problem .
after it warms up for a few minites , drives for a half mile ,
blue smoke comes from the drivers side pipe for ten seconds
then stops smoking , all seems fine . This happended twice now
in a row at start up .
About 8000 miles on a Pro bult thats five years , Edelbrock heads ,
typical cobra motor , driven lightly for years , then a quick trip to the track
hit the limmiter a few times , so what do you think ?



Thank you !