http://upload4.postimage.org/59747/correctionfactor.jpg

Here it is.
CF ? ignition correction factor. This it when you NEED to activate WI to deal with detonation. This is run with timing not to aggressive. ECU pools the timing as per graph. 0-CF means all good. 1-9 is a reduction in timing trying to deal with detonation (knock).
Based on this, WI only needed from say 4500 RPM till 7000 RPM.
Pump with PWM will easy take care of this.
You will run in to the problem if you will lean the mixture out and add more early timing to make more HP. Than your WI will have to start a lot earlier as detonation probably will show up at lower RPM range?

Coments anyone??

P.S. Appology for funny English, I am russian :oops: