poss gearing advise plz
 

i am running the tm4 with centre gear.im using a 80t spur x 8.5t motor 120a speedo all turned down for indoors mostly carpet but some slippy.i tried using a 25t pinion but the motor was getting on the hot side.
motor seems 55.(i know thats not hot but,shell n chassis was all hot)
or is it a air flow prob???
esc 35
i am using 30k oil in the centre too so is that too light and causing spin up?
i have another car setup
9.5t x80t 26 pinion with 50k centre and this runs nice temps

It's not easy without knowing the track. but I'd probably run 300 oil in the centre diff, and a 23 pinnion. Motor will get hot indoors on carpet, and more aiflow can only help.