Higher octane help

[K240]

Is 91 octane better for 240s? On my 240s gas cap, it says to use higher octane, for better performance...Is this true, or does it just pollute more? Would using 91 octane give me crappy gas mileage?

[180fan]

I got away with the 87 without a problem. 91's just keep your motor detonating earlier. Heard the "higher octane = higher performance" myth before too. Just use what you need to and you'll save money dude. 91 doesn't give crappier mileage. Dunno though, maybe it was just a placebo effect, but with 91 in my tank the car felt a bit peppier. Probably placebo effect though.

[KDashy]

A lot of people say that 91 makes a difference, a lot of people just use 87. I think the knock sensors take care of it if you use 87 But it appears that you had your timing advanced, so I'd assume you would want to use 91 or you'd suffer from some power loss...Not sure about gas milage though.

[w1ngzer0]

I got away with the 87 without a problem. 91's just keep your motor detonating earlier. Heard the "higher octane = higher performance" myth before too. Just use what you need to and you'll save money dude. 91 doesn't give crappier mileage. Dunno though, maybe it was just a placebo effect, but with 91 in my tank the car felt a bit peppier. Probably placebo effect though.

yep exactly.

[Zydeco]

when I use 89 it dosent seam to have the same top end grunt like between 6000-6900 rpm as it does with 91. that just what I feel anyways.

[w1ngzer0]

and higher octane doesn't clean your motor that is a myth as well. It builds up the same amount of carbon as 87

[K240]

thanks guys =]