Originally Posted by 92TypeR

Only if you are knock limited on pump gasoline, then a higher knock resistance (high octane) will allow for higher cylinder pressures and thus more power.

For example, my motor reaches MBT at ~32* BTDC. I begin to see knock at around 36* BTDC. That means, that even if I could tune to 40* BTDC, I wouldn't gain power, because my setup likes ~32* BTDC for best torque.

E85's higher latent heat of vaporization will allow for cooler intake charge as the ethanol converts from liquid to gas phase. If you reach MBT on pump gas before knock, this is how power gains would be made using E85 on N/A setups, not from increased ignition timing.

I do not think methanol injection is ever a good idea. It seems like a band-aid method of reducing the knock characteristics of low octane fuels. If you are on the cusp of knock, a higher octane fuel is the most intelligent solution. Of course, the people running methanol/alcohol injection aren’t looking for the best solution, they are looking for the cheapest.

Water injection is even more asinine. You are injecting a non-combustible, non-compressible liquid. Please don’t.

OP - You can run 12.5:1 compression on 92 octane without sacraficing ignition advance/power, only if you run a good cam combination that allows for proper valve timing. I am running Skunk2 Pro-3's with 12.1:1 compression, and I am not knock limited with ignition timing. Choose your fuel, choose your compression, then choose your camshaft. That is the correct order.

Originally Posted by KartelB

Wouldn't the same be true of a NA build where the compression is a bit high(12:1-12.5:1) and the water/methanol mixture is used to " curb detonation on high compression setups where the octane is less than desirable"? Would the same principle hold true? Boost and high compression in this instance create the same problems and can be corrected using the same techniques. Please correct me if I am wrong.

Originally Posted by 92TypeR

OP - You can run 12.5:1 compression on 92 octane without sacraficing ignition advance/power, only if you run a good cam combination that allows for proper valve timing. I am running Skunk2 Pro-3's with 12.1:1 compression, and I am not knock limited with ignition timing. Choose your fuel, choose your compression, then choose your camshaft. That is the correct order.