I have a switch that will turn the fans on 50% - if I had them running at the track or dyno in between runs, would it drain the battery? How long would they run?

 

Not sure but I know if your battery is not fully charged you'll run out pretty fast. I ran mine between runs evertime I went to the track and one day i ran em too long and it died. I had to get a jump and everone behind me was pissed. LOL... Just keep one of those lil battery packs with ya at all times and you'll be fine.

 

I run one of my fans at the track when cooling down for about 10 mins. or so but I have a 980CCA battery and so far (knocking on wood) it's lasted JMHO...Zed