I usually run 93 octane in my S2k, but last Saturday, I decided to try some 101 Unleaded. It seemed to have some more power (of course it could just be me "thinking" it was faster ).....but by running a higher octane gas, do our ECU's detect that and advance the timing accordingly? If so, maybe I wasn't dreaming that there was a little more get-up-and-go with the 101. Also, are there any side effects of running this fuel? I don't think there is, but it doesn't hurt to check......I won't be running it all the time, too $$.

 

Unless you are running a different ECU or Forced Induction I doubt there are any gains with 100 octane. Maybe a nano-second better throttle response. Higher octane will buy some tolerance before the spark map is retarded for really hot intake temperatures. (Think 100f+ days in the desert)

The ECU is notified if there is knock or unburnt fuel but it has no way of knowing you are running 100 octane. Several of the sensors can notify the ECU of symptons that you are burning lower octane gasoline. On the other hand, I don't believe the ECU can sort out the symptoms and run safely on 87 under load.

 

Hmmm, that brings up some good questions........

What DOES the ECU notice? I'm sure it tells if there is knocking....but what else does it do?

I'm sure the cool night also had something to do with the better performance as well. I'm headed to the strip tomorrow.....so we'll see what happens.

 

So sorry but I could not resist.

Knock, Knock.
Who's there?
ECU. ECU who?
ECU do you know what I do?

 

[QUOTE]Originally posted by Vtecnrg
[B]So sorry but I could not resist.

 

[QUOTE]Originally posted by JeffsS2k
[B]Hmmm, that brings up some good questions........

What DOES the ECU notice?

 

You want the lowest octane you can run without knock. Race gas will only help an S2000 on a really really hot day.

 

Antilles, generally but not universally true....

 

[QUOTE]Originally posted by Antilles
[B]You want the lowest octane you can run without knock.