Knock sensing

Give input on tuning as well as any tips and tricks you may have. Also feel free to share base mapping files for various engine types.
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Cpur
Posts: 51
Joined: Wed Dec 06, 2017 1:55 pm
ECU Model: S100 Pro

Knock sensing

Post by Cpur »

I am currently installing an S100 to my Cosworth yb, The original ecu used to use a knock sensor. Unfortunatly DTA does not support knock.
Is it so important to use knock?
Also i found a GM module that converts knock frequency to analog voltage which on GM is used to retard timing. This can easily be inputed into the analog in , but can I make a table for retard or correction when knock is detected?



Thanks and regards

Cpur
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Knock sensing

Post by stevieturbo »

Important ? Yes and No....depends how reliable that detection is, and what you want it to do.

Or if the tuning etc even warrants it in the first place.

You could use an analogue input to retard timing if your detection device offered a suitable 0-5v signal.
Would it really be fast and effective enough ? Who knows.

Build it right, tune it right and there shouldnt be any need for knock control, and even some systems that claim to offer it....they can vary hugely in their actual abilities. Some are crap, some are great.
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Knock sensing

Post by Rob Stevens »

Yes as Stevie says tune it right in the first place, on the fuel you intend to use. I don't think that using an analog input would work very well as you have no damping or other 'detection windowing' features to help control the applied retard. In a simple setup you could probably use the ana input to help log any issues and review later.
Cpur
Posts: 51
Joined: Wed Dec 06, 2017 1:55 pm
ECU Model: S100 Pro

Re: Knock sensing

Post by Cpur »

Maybe if not fast enough, i would make it at least lower the boost and give out an alarm. I dont know how the original cosworth ecu was using it, if actually active or maybe long time adaptive, to adapt to the octane content.
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Knock sensing

Post by Alex DTA »

Rob Stevens wrote:Yes as Stevie says tune it right in the first place, on the fuel you intend to use. I don't think that using an analog input would work very well as you have no damping or other 'detection windowing' features to help control the applied retard. In a simple setup you could probably use the ana input to help log any issues and review later.
Roib

You can use a Plex Knock Monitor (or Phormula K) with an analogue output in to the ECU.
You can't connect the knock sensor directly, it requires all sorts of processing.
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Knock sensing

Post by Rob Stevens »

Indeed, I didn't think that I needed to mention that you couldn't connect it directly.
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Knock sensing

Post by stevieturbo »

As Rob says, just build it and tune it right and it shouldnt be a concern.

If you want an alarm of sorts, then the likes of Plex, Phormula, Knocklink and many other such devices can offer you a standalone alarm system.
Most will offer some ability to connect to the ecu which as you say could maybe reduce boost or timing etc. Not to say it would have no value doing this, but I wouldnt be relying on it and tuning close to the ragged edge.
rocar
Posts: 107
Joined: Sat Sep 10, 2011 8:20 am

Re: Knock sensing

Post by rocar »

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