Modern car engine management is preprogrammed to run on a specified octane. For our purposes let's use 93. So you put 93 in it, and it's quality fuel. No pinging/knocking. The knock sensor doesn't have to adapt the ECU for anything. Next tank of fuel, you can only get 91. Obviously this isn't ideal. There will be some preignition of the A/F mix. The knock sensor reads this, and backs the timing down as needed.Originally Posted by jediali
That's all the KS is able to do. If IWAARS really wanted to get the maximum potential out of this beast, he'd need to re-dyno tune the motor's management while using quality 95 or 98 or whatever's available octane.
Putting a higher octane fuel than required in a motor is not required, and you will see no benefit from it at all.