What exactly does the "knock attack rate" do? For example: 1200 RPM / .18 degree/msec. Would this mean that at 1200 RPM if the knock sensor senses vibration it will retard the timing .18 degrees per millisecond? Or am I not on the right track?

 

You're on the money. FWIW, the knock recovery rate is in %/second, which means that the amount of timing removed is added back at X% per second. I have mine set at 100, 100, 150, 200, and 200. These are way higher than the stock values since it took too long for the computer to add the timing back in, which killed power and my 1/4-mile times.

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Greg Westphal
'87 IROC 305TPI/A4

 

Also, in trying to control knock retard, you can play with the Max Knock Retard vs MAP or RPM.

 

Thanks guys. That helps out a lot.

 

Now that I understand what it does, would I want to increase or decrease the values?

 

I left my knock attack rates alone for the most part. I figured that if I got some real knock, I'd want the computer to pull out enough timing to "extinguish" it, then add the timing back in really fast with the high values in the knock recovery rate table.

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Greg Westphal
'87 IROC 305TPI/A4