.. water-methanol injection ?? ..

My friend is running it on a supercharged application in road racing. During some chassis dyno runs we did it actually hurt power output. It may not of been set up right, I don't know, but we still use it to cool the intake charge and to help with detonation issues as the motor is some what high compression and running 8 pounds of boost.

For the horsepower your running, if you don't have detonation problems running your fuel and the optimum timing. I don't see you gaining horsepower on the meth/water injection alone. I'm no expert on the subject however maybe someone else will chime in.