Extended Use of Racing Fuel

I know, I know, this is a 911bbs, but I do drive a front engine Porsche. The question I have for you guys is twofold. What is the active ingredient of 104 or other octane boosters and is there a detrimental effect to using racing fuel constantly. The reason I ask is the price of gas is getting really high. If I'm going to pay that much, why not racing fuel? A buddy in WI puts it in his Chevelle (12.5cr, sub 10 quarters) and was telling me that it's now almost the same price as premium. It's odd that the price of racing fuel has risen only $.03/gal in his area while premium has risen by about $.75. Any ideas??

Dave951M