new problem

[gasshead]

i snagged my MM 7700 from my M0-3 for my slash, gearing is stock running 2.2 bowties ran fine in the mini now it just coggs from a dead stop and dosent seem to completly spool up tried 3300 6,7, 8 cell packs. then a 2 and i beleive we even tried a 3s lipo all the problems were the same regardless of battery. it almost seemed like the amp draw was too much for anything to work. what should i try next?