s300 knock sensor with a p28. analog input possible?

s300 and SManager software questions & answers
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Bubleguy
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s300 knock sensor with a p28. analog input possible?

Post by Bubleguy » Sat May 10, 2014 12:48 pm

hi guyz,

as i cannot re-open a topic (viewtopic.php?t=6648), i open this one to continue the conversation.

The answer made to the topic question by spunkster was "no". But i don't get the idea. Is it an electonical constraint? or a software limitation?

Why the analog input cannot be used for a "non-stock" knock-sensor as it can be for lot of gauge/sensor?

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Hondata
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Re: s300 knock sensor with a p28. analog input possible?

Post by Hondata » Sat May 10, 2014 5:36 pm

The knock processor needs to know the exact engine position, cylinder firing, engine load and rpm in order to distinguish knock from other engine noise. Basically a knock processor will look at the noise around peak pressure (~20 degrees past TDC) and compare it to an interval where knock is not likely to occur. It also has a band pass filter based on bore size.
The s300, whilst having analog inputs, does not have knock sensor processing capability, and it does not know the engine position to the accuracy required to implement a knock gate.
Hondata

Bubleguy
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Re: s300 knock sensor with a p28. analog input possible?

Post by Bubleguy » Tue Jun 03, 2014 7:52 am

Ok, thanks for the clarification.
What i had in mind :
As we can disable knock sensor from smanager, i thought s300 could communicate the sensor analog signal to the ECU at and defined time.
For example :
at T.0second : analog input is 0.1V, S300 send this value to the ECU
at T.1second : analog input is 0.1V, S300 send this value to the ECU
...
at T.Nseconds : analog input is 2.4V, S300 send this value to the ECU -> the ECU now the engine position, cylinder firing, ... and then can determine if knock occured or not.

Seems i was totally in error :)

Carchitect
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Re: s300 knock sensor with a p28. analog input possible?

Post by Carchitect » Thu Jun 19, 2014 6:46 pm

Is there a method of switching to the newer non-resonance wide range knock sensors. The ones with the thru 8mm hole? I have a method of fastening it to the engine but the output characteristics are different between the narrow range 1 wire knock sensors and the newer 2 wire knock sensors. The 1 wire knock sensors generate too much noise at any range over 4000 rpms to be able to successfully any sort of knock events.

Is it possible to modify the knock board or adapt a new board to the ecu to allow this to happen? perhaps even have audio jack output to sample it via goldwave the same way Motec SKM system is designed.

Thanks in advance

-Joe
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