PN Racing 32-T Motor only lasts about 5 seconds
 

before you have to let it sit for another 10 seconds to run it again.

Its a street board, 2x3 FET stack.

Full throttle lasts like 4/5 seconds and you have to let it sit to get another 4/5 seconds out of it. I did my own FET stacking. Is this a problem with the FET's? Did i ruin some while stacking...IE - leaving too much heat on them too long while installing them?

bump? i ordered another set, this time 2x2's and continue to have the same issue. Servo, this time, is running all of the time.

It's likely the radio reception from your remote. this cutout happens when the remote cannot output a clear signal to the board. try a fresh remote battery, and fresh car batteries. if it still doesn't work then it's possible you guessed it right with overheated chips (they can really only take around 10 seconds or less of solder heat.)