Hello everybody, I'm in the process of buying my local track and shop and at the present time there is two tracks. First is a 90 ft. tri oval and donut combo the second is a 145 hill climber track plus has quarter mile drag strip. The first track is powered by battery already but the hillclimber and drag strip both run off power supplies. which by testing the drag stripp it won't handle 2 group 20's at the same time... So here is my question I want to go to battery on all tracks, How many per track and what size or cranking amps should I be looking at. Oh by the way this track is located in Harrison Ar. so if in the area please stop in and say hello Well thanks for advice