So what happens if I toss some 100 octane into a stock motor?

[big_greasy_taco]

..

[blmlozz]

octane simply measures the fuels resistiance aganist knock.. you could use 100 in a car designed for 93 all the time if you wanted.. and could afford it, but there wouldn't be any difference from it being 100 octane.

[biketsai]

X2, what he said.

[big_greasy_taco]

Oh ok... guess ill just get it for the formula car then!

[AWDios]

If anything the car just may run crappy and not get very good mileage. It's a common misbelief that running higher octane is better for a car or will yield more performance. Your best bet is to run what it's designed for. Same goes for a car that takes regular, not good to put premium in it.

[Don Supreme]

Nothing good.