I had a similar issue with my GT2.0 Pro. I wanted to gear it quite high, so I reduced the timing to try and keep the tempurature down and found that if you reduce the timing from the factory settings, the motor actually ran hotter!!!
This was with an early version of firmware. I've now updated to the latest (1.38) with boost and turbo mode, and reducing the boost timing does make it run cooler as expected
