I have no experience with that EMS but with any tuning you have to break it down and start there. Knock threshold is going to be at what vibration or intensity it considers knock and puts out a value. Advance retard would be how much timing it pulls per unit of knock. Max retard allowed is how much it can pull in the worst condition(max knock). Rate of advance increase is how much timing it adds until it sees knock.

Hope that helped at least a little bit. That's how I see things anyway.

The knock sensor does not measure vibration directly. It is a microphone that reads noise and outputs a voltage. That voltage signal should then be filtered by the ECU to determine at what values knock is occurring. Then the tuner can decide from there what to do when knock happens (i.e. how much timing to pull, fuel enriching, etc.) The factory spends a long time calibrating this to get it right. For example the 98-99 black box ecu has over 9 filtering maps for the knock sensor.

The problem is that you can't just go by high voltage = knock or anything simple like that. The engine has so many other forms of noise from the valvetrain, turbo, etc. that you have to come up with a filter that can pick out specific peaks as knock and not others. This is specific to each engine and when you modify things too far from their original state then the calibration no longer applies as well.

This can be seen when people install forged pistons and other internal performance parts that create different noise from the OEM parts. Then they find they have phantom knock issues where the computer is measuring knock and its not actually happening.

The moral of this all is that setting up a knock sensor is very difficult to do properly and even more so from scratch on an aftermarket EMS. They all do it differently. Megasquirt offers some preset tables for knock sensors where AEM you are on your own to set it up. I'm not familiar with your EMS but finding other people who have set up knock sensor using it on other engines using it and then applying that process to your car is probably going to be the easiest way.

Knock is a very specific frequency and is purely based on the speed of sound (or mach number) inside the combustion chamber.

When knock happens it sends a shock wave out....that shock wave bounces around inside the cylinder. All shock waves travel at exactly mach 1.0 and is related to the pressure (has to do with the density of the gas) its traveling in only. Since its bouncing back and forth very very quickly (mach 1.0 at sea level pressures is 761 mph) it produces a frequency that a knock sensor "microphone" can pick up. The knock frequency is related to the bore size only since the shock wave is just bouncing back and forth between the cylinder walls.

Most online knock calculators don't tell you what pressure they are using for the density of the gas to determine the frequency, but its in the 1000's of PSI as knock happens at peak cylinder pressures and at those levels mach 1 at 5000 psi is pretty close to the mach at 5500 psi.

85mm bore 4G63 knock frequency is 6.7 kHz
87mm bore of a 4G64 bored out 0.020 knock frequency is 6.6 kHz

So as bore goes up the frequency goes down as the shock wave takes longer to bounce back and forth due to the increased distance between cylinder walls.

As @95REGF150 stated some components can cause phantom knock due to harmonic resonance in the part itself. Everything has a natural frequency to it that will cause it to resonant such as pistons, bridges, and even buildings. Its also the reason our DSM's have rubber timing belts as chain driven belts cause a lot of noise which back in the 90's they had not figured out how to filter out...or at least not how to do it cheaply.

That being said, I have no idea what your EMS parameters mean for knock as some aftermarket knock "computers" just let you pick the frequency as knock is a calculation.

Aside: I used this website for my knock frequencies. If you want to calulate a more accurate number you'd need a lot more info so its more of a close ball park figure.

http://www.phormula.com/KnockCalculator.aspx

Thanks, I really appreciate the info. Will do some research.