How much run time will I get running my SLASH VXL with stock 23/86 gearing on ASPHALT for the following:

Lipo 2s 7.4v 5800mAh 25c?
Lipo 2s 7.4v 4000mAh 25c?
Lipo 2s 7.4v 3300mAh 25c?

I would like to upgrade from the 7 cell nihm(getting a good twenty minutes of run time) nihm to a lipo without over heating my Slash VXL 3500 Velineon motor. I would like to have good asphalt speed without worrying if I'm over doing the motor. If you all could....please help with runtimes and proper gearing options. Any suggestions? Thanks!