from sport compact car:
is this cheaper alternative to race gas? has anyone tried using this?Octane
SR20DEs are not as good as the Honda B-series at running ludicrous compression on 91-octane pump gas, so making this engine happy requires careful tuning and a little bit of octane enhancement from our old toxic friend Toluene. Toluene is "look at me sideways and I'll give you cancer" nasty, and is commonly available through paint stores, where it's sold as a solvent. Toluene also happens to be 114 octane, and is a common ingredient in octane boosters, as well as one of the more important octane enhancers in Japanese fuels. Remember those crazy 1.5-liter, 1,500-hp F1 engines from the '80s? They drank mostly Toluene, which also has particularly good resistance to detonation.
Internet wisdom dictates that when mixed with 91-octane fuel, a 30-percent ratio of Toluene will yield a 97-plus octane mix. Oh, and this doesn't get the thumbs up from the EPA, so the cops who test your fuel when they pull you over can write you a ticket or something. Yeah, that'll happen.