I am looking for a offroad .12 engine for my xxx-nt sport rtr 2 so it has to be a RE engine. I will spend up to $150 but could be $20 flexible. What is a good engine that will outperform my Mach .15RE and be easier to tune and better fuel economy? I noticed that the mach .15re has .85HP and the TG only has liike .7HP. What does horsepower affect and will it be more powerful than my mach .15? Any other suggestions on engines? I will be racing.