After a night of racing, I leave the pack alone.
Before i charge them again next week, I put the packs on the lights, then when it cuts off, I put the pack on the discharge tray for about 30-45 minutes.
Try to time it so you take the pack off the tray about 10 minutes before you charge.
Lowest mv setting possible. In fact, after this discharge technique, the packs will take a full charge (notice if you don't fully discharge you get charge reading of 2500 mah at peak.) . If you cut the pack off early, I notice more punch! Stop them at around 2700 mah. Thats really plenty of juice for stock and most mod, unless your running 8t motors