Changing the throttle EPA is not recommended by CC.
1. I bought the Monster Max system and it's way too fast! How do I "tone it down"?
Answer 1: Lowest timing advance, smallest pinion and largest spur gear, and experiment with punch control. Always do these three things FIRST. It's not a good thing to dial down the top throttle endpoint, especially when you can re-gear, or just go down in cell count.
The batts, the ESC and the motor will all run hotter than normal in a system with turned down endpoints to slow it down. The ESC is thermally protected, but the batts and motor are NOT.
I don't think that means that you can't do it, but it's important to note that it's not recommended.