I'm having a problem, car have a bad oil smoke.I've did a ring and valve job but still smokes what could the problem be thanks.

If it's white smoke, it may be the Transmission Modulator, with it leaking, intake will draw transmission fluid through engine.

If you see blue smoke, when you start the car and when you accelerate, the valve seals are likely bad. If you see blue smoke all the time, there's a problem with the rings. White smoke is coolant being burned.

I agree with txgreasemonkey, who did your ring and valve job?

How thorough was either job done?
If valve guide clearance and/or piston to bore clearance is excessive, you won't get a good result.
Also, are you certain that it's oil? A car that is running to rich will smoke very similarly.

Compression test may reveal bad rings. A compressionn test with oil in cylinder can narrow down from bad rings or valves.
What color is the smoke?