all around set up
 

i dont race, tired of checking temps, 35 mph is fine, good runtime on 12 cells, i have a 9920, what motor would do this

and gearing per motor, this set up is for an e-maxx stretched to 14 in so it it has a little more weight than stock

thanks

Check out this link. It should help you figure out what you want.

http://scriptasylum.com/rc_speed/_motor_selector.html

I entered some estimated values and came up with a 7xl motor. That should get you what you are looking for. On 12 cells it should wind up getting to approximatly 30K rpm. Thats a fairly conservative RPM and should still run plenty cool.

thanks, that 7xl seems to be a winner for 12cells, i have never seen that chart before i'll check it out

I would also vote a 7xl.

I wouldn't discount the 8XL either. If you decide to go to either 14 cells or even 4S lipo, the 8XL does very well in a truck. I just replaced the 7XL in my Monster GT conversion with an 8XL. I like it better, but I'm running it on 4S lipo.

most of the time i will be in second gear likely in a field, maybe find a sand dune and put on the paddles, would the 8xl be more at home, with a little less amp draw as well. also i do run a ubec

7xl is (abit) faster but (abit) hotter. 8xl is a good choice too, esp if you are worried more about heat/runtime than all out speed. I have a 8xl, and even on 12 cells it still moves. Considering you want to run in "harsher" conditions like grass and sand dunes, I would go 14cells/8xl and undergear a tooth IMO, but that's me.

I don't know anything about the gearing on trucks and I know that the general rule of thumb is to lock the truck into second gear when converting. Since I built the MGT for my 8 year old son, I didn't want it to be too fast. I locked it into first gear, am running the 49T spur with a 16T pinion on the 8XL with a 4S lipo pack. The only thing I accomplished was to make it a beast. It goes over anything, wheelies on demand (even at a good clip) AND it's still pretty fast. I'd guesstimate around 30 mph.