What Amp Size and Brand Controller for EMP Motor


New Member
I have a 93 Marathon, 6"lift, 22"tires with a two speed EMP motor, 275amp curtis. Needing more torque, what amp size and brand controller would you recommend? 400, 500, 700 Alltrax? or 480, 700 Logisystem? I was told by EMP the motor would only pull 300 or so amps and that a 400amp controller would be all I needed. Anything over that would be a waste of money. Just wanted to get some real life opinions. Also is there a kit or something to give me posi traction?


A 400 or 500 amp Alltrax would work well with the EMP. If you're ever planning on going with a high speed or torque motor you could get bigger now so you don't need to upgrade again later.


New Member

So are you saying that they only way to get a significant increase in torque is to convert to 48v?


You can get a 30% or more increase in torque with a D and D Stealth Stalker or GE Beast motor and a 650 Alltrax or 700 amp Logisystem controller on 36 volts but you will need to do both upgrades. 2 gage cables and HD F/R and HD solenoid also. You will lose some speed with these setups but your torque will be killer. Add 48 volts to these setups and get even more torque and regain the top speed.


Well-Known Member
On a stock 2hp motor? YES.

If you are changing motors also, then only the motor mfr. can make a claim to it's power on 36v.