This is from a very smart man (Sid Waterman told me this and it verified what I was seeing...I mention this because I've never seen some of the huge gains from alcohol as many claim but it's possible I just suck at engine building and tuning) and matched pretty close to what I already was finding.


Best carb gas to best carb alcohol: 3-4% for alcohol.
Best injected gas to best injected alcohol: 3-4% for alcohol. So that means...
Best carb gas to best injected alcohol: 6-8% for alcohol. So...if you are making 600 HP on carb'd gas and you switch to injected alcohol and both the carb and the injection is [censored] on tuned up you'd make 648 HP BEST CASE.

In practice, since I was building and tuning high RPM small block stuff, it was a [censored] to get the fuel curve correct without a minimum of three by passes and I could have used one more. I did play with slowing the pump down a bit, but the car got sluggish in the gear change. I was shifting at 8500-8800 at that time. There is also getting the by passes to not only open at the correct time, but they have to close at the bottom of the gear change (4 speed) at the same time and then open again. Much easier said than done.

In the end, I would go back to carb'd gas on a tunnel ram and not screw with it.