There has been a lot of talk on this forum about knock retard and the mysteries associated with it. 1st of all I would like to thank Dennis Leek for contributing the stock ecu knock information that I am about to discuss. To sum up the stock ecu infomation we have to think mentally what is going on at 6000 rpm for an example. At 6000 rpm we use a 3 tooth reluctor, so we actually have 18000 spark events per minute at this speed and if we divide this by 60, we get 300 sparks per second or .3 sparks per ms of time. The stock ecu needs 5ms to recognize you have knock present and another 12.5ms to actually process the retard between knocks, so in theory 17.5ms of time has gone by since the 1st knock event, before any retard has taken place. This is 17.5ms x.3ms=5 spark events or 5 cylinder firings with "knock". Next is the recovery time is every 200ms, which means you have 200 x .3ms=60 spark events with reduced timing before the timing is put back to normal after not seeing knock.
What the JS box does, is that it can see the knock instantly it does not have to wait 5 firings to retard the timing, it is done on the next firing, and the recover rate is done on the next firing also. So what this means to me and you is that the timing is pulled 5 times faster and recovers 60 times faster at 6000 rpm with a JS box. If some numbers don;t make sense please correct me. If we could get John from J&S to chime in here to verify this would be even better.
What the JS box does, is that it can see the knock instantly it does not have to wait 5 firings to retard the timing, it is done on the next firing, and the recover rate is done on the next firing also. So what this means to me and you is that the timing is pulled 5 times faster and recovers 60 times faster at 6000 rpm with a JS box. If some numbers don;t make sense please correct me. If we could get John from J&S to chime in here to verify this would be even better.