When I shut off the car I get a little bit of smoke coming out of the carb and through the cowl induction door. I notice it when the motor diesels a little when you shut it off. If I let the motor run for about 15-20 seconds before turning it off it usually won't diesel, but I can't remember if I still get the smoke. What could this be from? The dieseling or something else?

When the engine diesels it is turning backwards and pushing fumes back out through the carb. If you lower your idle speed you can usually stop the dieseling. I run a higher than stock idle speed because of my lumpy cam, so when I shut my engine off I turn the steering wheel just enough to put a load on the power steering pump which lowers the idle just a bit and it shuts off without dieseling.

So its probably the dieseling thats causing the fumes through the carb? Good to know...I thought it might be something more serious. I have some carb tuning issues to take care of as well...I think the idle mixure is way to rich, along with the cruise mixture.

Read my post here: http://www.chevelles.com/forums/showthread.php?t=86216 for one way to deal with dieseling.

Good call...I remembered reading somewhere on here that it is caused by too much timing, but that makes sense what you posted. Thanks for the clarification ;)