Motor running to hot, not sure what to make of it

[Ola]

Ok, since i didnt have higher gear`s to test right now, i had to test something else..

So i charged a set of 3s batteries to try and run 6s.
Hooked up hotwire, and reduced current limiter to 75% (perhaps i should try even lower?)
Timing is set at 0dg as last on 5s, and throttle curve 2.

After a hard 10-15min drive, allthough less full throttle since the car is ballistic on 6s :D, the temps where lower on 6s than on 5s.. I measured the motor to 150f and rx8 to 113.
The same gearing, making top speed 53mph on 6s.

Is 0dg timing the best to avvoid heat, or is it more effective on 5-8dg?