Originally Posted by eweisbard
Octane is for antiknock, if its not knocking whay do you need more. Here is something else that I learned a a training school. Ocatne makes fuel more stable to prevent autoignition, meaning ignition from a source other than the spark plug like a hot piece of carbon. Too much octane can actually cause an adverse effect by making fuel harder to ignite reducing performance. I have tried it with absolutly no effect in my 2.0 zetec. Dont assume what people know or have tried.
People need to read the whole post this has been beat to death. The 2.0 Duratec computer advances timing till it sees knock. When you can advance timing you will see a performance gain. Obviously you need a motor with more compression to utilize the higher octane and this car has a 12to1 motor. If it were a 9to1 motor probably wouldn't see much gain. I don't know what zetec's had for compession but am betting alot less than 12to1 or if they had the avanced cam controls these motors have, that also makes a difference.
65 Racestang 2012 Focus SE HB Sport Pac 5 speed man. NewMission Cold Air, Custom 3" Magnaflow exhaust, Steeda Rear Sway Bar, Eibach sportline springs, Steeda STS, Axis wheels, Blox shift knob, Focus elecrtic RMM, Injected 93 Tune V1 176HP 152Torque