Got a 70 chevelle 396 has new alternator, new battery. Everything work great until one day at the track. Now I have problem keeping my battery charged. Whats weird about it is my generator light comes ON when the key is in the off position but goes out in the on position. I have not messed with any wiring for a long time, this just happened. any sugestions!!!!!!

Guessing regulator. Follow Peter's method on this page and post back the results. Do you have a wire from battery (-) to the right inside fender?
http://www.chevelles.com/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic;f=22;t=002353;p=4

yes it was the regulator thanks very much
Andrew