Higher octane gasoline, What does it do? Options

[YellowTwo]

I always hear of peolple with performance type engines using higher octane gas, so what does it actually do? Does it make the engine run smoother? or cooler? or improve horsepower at all? And what is the difference between lower and higher octane gas anyways?

I'm just curious. I really doubt I will be using anything other than the cheapest gas since gas prices are so high

[Negative]

I hope not. My car just hit 50,000 and it is running better than when I got it at 33,000. It wasn't until I added the intake and the exhaust that it started that s**t. It runs perfectly on 93 octane and ok on the middle grade but ****ty on the cheap gas. Some of my other friends with fixed up imports have the same problem. Also my '95 celicaGT did the same thing after it got it's upgrades. I don't think it's indicative of other problems - some people on this sight just seem to think that because they're cars do or don't do a certain thing that it can't possibly be true. Kinda like that myth that an intake like mine doesn't do anything but improve the sound - just because theirs didn't improve doesn't mean anything.