Water / Meth injection

[rx8]

I bought a e92 335 in mid june as part of my mid life crisis experience. D car came with jb3 tune n dci( intakes). Doing a bit of research n modding bit by bit. So far have only taken out d secondary cats n replaced d worn absorbers. Sports exhaust n water injection is what i had in mind 2 do next. If water is introduced, i can run a higher map which i can adjust using d throttle. My worry is fault codes n engine issues but i think shd b ok so will probably do it next week at sunway. Thks 4 yr input ramsing.