build a gmaxx and i need help

[suicideneil]

Well, as a general/ rough guide for gearing things like the maxx, revo or flux with the MMM & 2200kv motor:

4s lipo = 40mph
5s lipo = 50mph
6s lipo = 60mph

Those are realistic top speeds for a truck in the 10lb region. As for actual speeds you should aim at, that kinda depends on the terrain and how much space you have. I use 5s lipo with the Medusa 36-80-2000kv motor, roughly equal in power to the MMM motor but a tiny bit slower; I gear for 40mph as thats plenty of speed for the space I have ( about a football field size area roughly ). 44/12 sounds fairly good for your setup, but you can always experiment a little bit up or down to see how you like the acceleration vs topspeed & see how the temps react; there isnt really a perfect setup or gear ratio, just whatevers right for you & what you're doing at the time.