What fuel are most of you Go Engine guys using? I'm currently using 30% Byrons race fuel but have been considering the switch to TQ Fuel. Can't wait for my Go .28, it should be here in a few days! It just so happens I'm in need of a gallon of fuel as well, so I figured now would be the perfect time to make a switch if I was going to do so. The price difference is 8 bucks though...not sure if it's worth that much or not. Also, which head shim should I be using with 30% fuel(or does it not matter)? If I'm not mistaken I think I read that there were 2 shims included with the engines.