I have just installed the PSI ECU monitor which includes a Knock Correction value in degrees. When driving normally it stays at zero but when you boot it increased to 3degrees.

Can anyone tell me what this actually means and the implications. I drive a STi 5 which is only fed Optimax and millers OB

Cheers
Za

 

Is it plus 3 or minus 3?

 

Sorry John dont think it states. Certainly doesnt have a a noticable minus notation.

 

Check with the manual or manufacturer. The difference is important. If running +3 it suggests the ECU is quite happy in some particular zones to advance the ignition. -3 is acceptable but suggests you need more octane. Of course the knock correction can be different in each load and RPM zone, so a single value doesn't tell you a huge amount about how your car is running, max/min more helpful, really you need to graph it across the RPM range for it to be useful.