Hey guys, I'm new to the Nitro scene, been racing electric for 6 years. But I have a couple of questions. I have an RC10GT I got slightly used from a friend (5 tanks)

What is the best tuned exhaust to get for the stock RC10GT Engine? And what would be a good next engine that would work with the same exaust/header setup? Also, what type of fuel is the best to run at a high elevation (5,000ft), I've heard Blue Thunder is good just want to hear some opinions. I just have some traxxas 20% I got for real cheap, but I want something different.

Thanks alot!