z17

so i buy this 280zxt(81) and 280z(77) for $600 bucks. both work. its just that one needs an o2 sensor put on, and the other, a starter. well me and my dad start working on the turbo one. so we put the sensor on and smoke comes out of the exhaust. so we check every thing and turns out, theres to much oil in the motor.but we smell the smoke, and smells like burnt gas. so we check spark plugs, and about two of the spark plugs were wet of oil and it smelled like gas too.well i also saw the oil line going to the turbo, wet of oil where its connected at the oil filter or some where around there. im going to drain the oil a little bit today and see if thats the problem but my dad talked to one of his friends that is a mecanic and he said that some how the gas might be mixing in with the oil. then i also heard that it might be my valves. and if its my valves then i might just get a new head. but we know it has to do with the gas and oil, that its running to rich. but we bought a new sensor to see if that was what it was make the gas rich. but we got nothing. just smoke that smelled like burnt gas. if it is rich... damn, but we got a brand new sensor!!! ill keep ya posted to see what happens after i drain a little bit of the oil out. my ears are open for opinions. any thing.