In Reply to: Re: I thought the knock sensor advances the (m) posted by aiiee on March 02, 2001 at 10:17:57:
So the writer of the attached message is mistaken when he says "the timing will advance itself to take advantage of the higher octane"?
No, he's right, read the whole statement:
"It Depends... On where the car is optimized, octane-wise. If the car was optimized for 96 octane fuel, and you were running 93 - you could benefit. Because the timing would advance itself to take advantage of the higher octane. Note that higher octane fuel helps not at all unless your timing is advanced to compensate for it."
There's no way BMW sets up the engines for 96 octane, everybody in the US would be running at reduced power unless they used aviation gas.
The bottom line: anything over 93 or 94 octane will not provide a power benefit.