Thanks for the reply. I also had this idea as well. Since I have to send in my mamba to Castle anyways to be fixed I could get a refurbished MMM for 100 and not have to worry about running that C-Tech pack in it and having it over heat. The 4s pack probably would be a nice set up but I dont want to spend 200 on a battery or the added weight of a 4s. With a 2s pack, motor and other electronics the truck weighs about the same as when it was nitro, and I really want to keep the weight as close as possible to that. Would the 1506 3.5d's temps be fine when geared 36 spur 20 pinion?