Hi Guys
Think there needs some clarification here as the RS uses very advanced knock control and in fact we add several degrees extra to the pcm’s ability to reduce ignition timing, not the other way. Also the knock sensor in the RS calibration is active until 7000rpm so always has control.
There are several conditions which can encourage knock these are mainly air temperature, fuel grade, charge pressure etc. It’s far more common for an engine to knock at low rpm rather than high rpm which is why in the majority of Ford calibrations the knock sensor is switched off at 6000 rpm as it’s deemed no further control is needed. Even the RS after about 5500rpm barely makes any corrections and if you log individual cylinders in most cases the pcm is adding timing rather than taking it out.
what can happen is these cars learn very quickly to be economical so when cruising along they run to a target maximum advance on a table called borderline knock table, minus several degrees. The pcm advances timing in some cases to the pre resonance of knock which is the frequency given off just prior to knock, the pcm from this data knows where to set the most efficient ignition point.
Now let’s say your cruising for 20 minutes at 75 mph constant the car would have learned and the timing will be quite far advanced, you then immediately give it a boot full of extra boost and higher charge temps mainly from low rpm and in most cases the pcm can adjust instantly but there is still a possibility a small knock may occur but mostly in lower rpm conditions. This can occur on the stock calibration too and is part of what the calibration is set up to manage.
Our Race tunes are two years old and no where near as refined as the later Ultima tunes DS Iltima is our stage 1 tune for std cars, DS Ultima 2 and Ultima 2+ were made on a car with intake and downpipe / sports cat although majority of standard and modified cars run Ultima 2+ as it’s the latest and best all round performance
as to the reference of another tuner getting knock on a DS RS, it was on Race 99+ running standard fuel, baking hot on a dyno and even the stock file made less than 300 bhp, the customer decided to get a custom map from that tuner that suddenly made all the power and at a grand later.
Enjoy the cars guys our maps are very well tested and there are several top calibrators behind them, personally I’d lean towards the Ultima maps they have more updates
all the best
TeamDS
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