The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting. The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel.

 

how embarassing, i was just getting ready to say the same exact thing. good thing i caught myself before i pushed the "OK" button!

 

ohh dont worry.. thats just proof that there are smart people on this forum

 

Actually I believe that the chip will take action and retard the timing, but I could be wrong.

 

holy cow where how you been?! Yeah the ECU will retard the timing to prevent engine damage. It will also reduce engine performance.

 

OMG that mod is back