I am used to the heat. Phoenix is in a record breaking 110+ degree 24 day straight run. 16 of those days have been 115+ and one day was 119. You just learn to take breaks, drink water ect. It sucks, but you gotta do what you gotta do.
Every performance vehicle I drive runs a blend of ethanol. The SHO runs e30, and the Lexus is e50. Only my Ford Focus ST runs on 91, because I do not beat on that car at all. It is my daily, and at 172K miles I haven't replaced anything major on it. Stock turbo, stock clutch ect.
With the Lexus, when it is this hot I usually run 15 psi of boost. It is still snappy and has little to no knock which is good and to be honest I don't really beat on it either. However during fall and winter we have had the boost up to 28 psi (with soft timing). At 28 psi the Lexus is out of fuel injector. Once the temps come down, we will start working on the full timing 28 psi tune. With the Cryo ring, DIY Water Sprayer, and the intake wrap, I am really hoping we can make a dent in the IAT's honestly in this heat, and get them down even more in the colder months.