PLEASE HELP ME!! (pick out setup)

[Finnster]

To repeat the already said:

Bigger batts: 20C 4800 (96A) is too small
Bigger motor: 1521 will do the job and stay cool. Muggy is a big truck
Be reasonable on speed. Do you really need 55? 45 is fast already.
Small tires will help

You are prolly pulling 2500W+ peak. That's a ton of power. Overall I would say the setup is a bit underengineered for the task at hand. I wouldn't assume a new esc/motor will fix it if the specs are not being raised. If you really want big reliable speeds, a MGM 160A/8S controller would be needed and a 1521. You could have bought it already w/ all the dead electronics you have now I bet. Else lower expectations

[mk351e]

people have mentioned the Neu 1521 a few times, but I don't understand why? I mean, if the 1515 has the power to make the truck fly (if I strapped wings on it), why do i need an even bigger motor?? What is the difference? Does a bigger motor run cooler? If so, why??