InitialD is right,
Here in Brazil all the championships run over 20% nitro, but im STARTING to prepare myself and my car for the preworlds (im not an excellent driver so i need at leas 5 years of preparation heh ehehhehehe) ... and the preworlds run over 16% nitro ... i just need to know the difference in behaviour of the engine cause i will buy a new engine just as the one im running now ...
cya !