Dad ran one of these in his Targa car this year http://www.alcoholinjectionsystems.com/
It allowed him to run 22psi all day long on 98 (instead of 19), and an extra 20rwkw. So in total it gave the car an extra reliable 40rwkw in total from the extra boost, timing, and octane boost.
the Kit he got was cheaper than most, and realy well put together.