I have spent some time with a BGX. You did not mention your intended rpm range so internal mods may net very little power. A tuned pipe is an absolute must if you want power. The BGX cylinder port timing and compression are ideal for use with a tuned pipe at 8000rpm with moderate nitro(10%). Its compression is very low so even more nitro can be used with a standard muffler for extra power and wider needle valve range. The BGX does have very short rotor valve timing at 173 degrees open, industry standard is closer to 190. Opening the rotor valve doesn't do much until rpm increases over 8000 though.