Can water injection effectively replace 100 octane race gas?

[91CavGT]

I currently own a 2003 Dodge SRT-4 and will be installing water injection on it when funds allow me to. I will be using a 100 psi Surflow pump, 2 selenoids, and 2 McMaster Carr nozzles(one around a 3 gph size and one around a 5 gph size). One nozzle(3gph) will be triggered at 5 psi and the other(5gph) will be trigered at an adjustable boost level(anywhere from 4-20 psi but will probably be turned on at 11 psi). I plan to use a mixture of 50% distilled water and 50% methanol.

The motor this will be used on is a 2.4L DOHC factory turbocharged 4 cylinder motor with 8.1:1 compression, a VERY small TD0416G reverse flow turbo, a decent sized factory intercooler(approximate demnsions are 3" thick, 2' wide, and 7" tall. Peak boost is going to be in the 17-21 psi area(I'm currently running 17 psi).

At 16 psi of boost, the car has already been dynoed at 242 hp and 264 ft lbs at the front wheels with air/fuel ratios being right at 10:1 from 3500 rpm to 5,000 rpm where it start to lean out a bit to 12.5:1 at 6250 rpm(redline).

Now to my question. The Mopar Stage 2 upgrade will be coming out for this car and will include some pretty nice stuff. It is going to be coming with 4 682cc injectors, a tuned PCM for these injectors, and among other things a switch inside the cabin for pump gas or 100 octane race gas. The race gas switch is supposed to alter fuel and timing when activated to give an additional 15 hp and 20 ft lbs. So, will this water injection system be able to replace 100 octane race gas and still give safe air/fuel ratios? I know this is a very broad question and there are many variables involved, but in general, is water injetion as effective as 100 octane race gas?

Thanx..........