I have been charging these type packs (NICDs) for over 10 years and 5 amps seems to be about the best rate anyway. That's what I have my charger set up for. If the battery has been sitting for a while (15 minutes or longer) but fully charged, you might want to top the charge off with a 7 to 10 amp charge if you can watch the charge rate rise and fall and stop the charging when the charge voltage on the pack starts to decline. Good Luck at Quaker Steak. I will be there February 13th racing in the Masters Legend Class. Hope to see you there.
Dan Nusekabel