A lot of pit buz that cooler fuel runs better.
METHANOL VAPOR ISSUE: We found in our methanol publication development that only methanol vapor burns. So much of the methanol in the cylinder is liquid, and large & small droplets. And not vapor. Anything that is not vapor does not burn. There is not enough time to vaporize. Furthermore, with liquid methanol in the cylinder, you get ignition vaporization at the expense of ignition.
MAYBE GOOD, MAYBE NOT: In some racer combinations, cooler fuel will be better. That would be the case for a hot day with an engine tuned to the edge of detonation. Yet in another engine, say on a cool day, that is somewhat rich and tuned with more spark advance than the norm, also tuned to a leaner idle than norm for more staging temperature, cooler fuel may not help at all. It will only reduce vaporization and make less power.
TEMP: Below 50 degrees in one atmosphere, there is little to no vaporization. Above 149 deg. in one atmosphere, there is all vapor. At boost and compression, different tune-ups make different temperatures and different amounts of vapor. There are so many different effects on vaporization and the horsepower result that a blanket rule will probably not work across the board.
REFERENCE: We discuss this in great lengths in our methanol publication with a lot of engineering and racer data. Over 30 pages provide Information about temperature. Over 60 pages provide Information about vaporization.
An extensive index of TERMS (6 pages single spaced) can be downloaded from our website; from the book description page. To give an idea of how vast the subject matter is.