I know for a fact that it really helped my Porsche 996 Twin turbo significantly in the hot months over 100 degrees because it was really easy to feel the timing pull back if knock was detected. It never pulled the timing back with toluene, even up to 198mph.... Haha. Had more room on the tach, but not on the road. It was fairly modded. I wanted to get to 200 at least once in my life. Close enough. Ran it for 7 years straight and not a single issue. Same with the Z. 7 years so far and she is running great. I'm a believer. I haven't seen any professional publications saying it's bad unless it's over 40% because anything that is not metal will melt. No rubber or plastic fuel lines at that %. Hahaha. Never a need to go that high.
