Hello actually this info actually helped me out to understand more about modding engines. the thing is that i just bought a novarossi 3sct, and i want to make it just like the tunned version or even better, i don't want to make my way to that point too hard. i was thinking about doing some milling kind of drops on the piston sleeve, opening the upper part of the exhaust port 1mm each side, and at last i'm planning to remove those 2mm on the crankshaft hole of the side that closes. ´cause i don't what to screw the engine, does any of you know what i should do exactly to this nova 3sct to turn it into the tunned version? or what i shouldn't do to it to avoid screwing it?

i really appreciate your help.