I have a friend who just bought a 88 S_10 with a rebuilt 350 motor. He doesn't know what was rebuilt,bored,cam, etc. It runs for about 2 minutes fine but after that it blows out oil from exhaust pipes you wouldn't believe. It makes me wonder if he has a bad intake gasket but he said he checked it out and it seemed OK. He's not a motor head really doesn't know much asbout engines and won't let any of us work on it because he wants to do it himself. I told him it could be the rings haven't seated, bad valve guides, if it was bored incorrectly, the cylinder walls could be scratched. Any other suggestions I can throw his way?