keep it cool

[captain harlock]

What is the best way to keep my 9920 cool and not extremely hot? in the latest run I made with my T4 with the 1930/5 motor and the 9920 ESC, the controller suffered some serious heat. I thought that the motor and the position of my controller in the chassis were the main factors. I've changed the position of the esc as well as the type of motor I was using( now the 1920/8 which I guess is a little torqier than the 1930/5) and I added a foam spacer underneath the esc to protect the circuit of the esc in its back and I used a nylon battery strap to secure the foam spacer to the esc and then I applied a double sided tape to fix the esc to the chassis of the T4. I tried the truck with the 1920/8 and guess what? the truck accelerates much faster now since I'm using a smaller rotor which is yet a bit torqier than the 1930/5, but the controller still generates heat. What are the reasons?

- Is it because of the additional foam base that I made for the thing to let it rest on the chassis in a much neater way and thus the foam spacer prevented the air stream from cooling the circuit in the back of the esc?

- Or is it because of the gear ratio which is 10.2:1?

- Or maybe because I ran the truck inside my house which its floor is covered with carpet and I kept using the brakes constantly?

- Or maybe you people know something I dont know and I would really like to get some help from you. Thanks a million any way.:)