If you have to, you can run your packs more than once a day but I really wouldn't suggest more than twice. I think you'd really help yourself out by getting at least one more pack. I know it's expensive but you can get a decent matched pack for around $40 or so. That way you can get 3 practice runs in and two qualifiers and a main and only have two runs on each. Some people seem to feel the second run on the 3300's give a little more punch but less runtime. I run mod so I need all the runtime I can get so I only run a pack once. What you'll want to do is have your worst pack charged the night before. (Not the bast thing for the cells but you do what you have to when on a budget
) As soon as you get to the track start your second pack on the charger. Run the first pack, and ass soon as you're done, discharge it and let it cool. But don't put it on a fan, then run the second pack and start the third. This way, by the time you need to charge the first pack again for qualifying, it should have had time to cool.