I have been playing around with some older GP3300 packs. I charge them on a GFX at 6V and .4 cutoff. I discharge at 30A to 5.4. I deadshorted one of the packs over night to see what results I got. I thought my IR would drop. My avg V increased a little. Are these packs junk for stock racing? Should I have deadshorted for a shorter time?