What are good tire sizes to put on a 1979 camaro with 14 inch rims the rear rims are 8 inches wide and the front ones are 6 inches wide?

Depends on what size you want. If you want bigger tires on the back than on the front, you can run a 235 or 245 60R 14 on the rear and a 205 or 215 60/70R 14 on the front. Of course this depends on the off set of the rims and if the car has been lowered. This answer is under the assumption that the car is stock factory height and the stock or normal off sets.