Knock Detection with variable sensitivity over RPM

A forum for discussing the MegaSquirt related (but non-B&G) board development, assembly, installation, and testing.

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ianferrell
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Re: Knock Detection with variable sensitivity over RPM

Post by ianferrell »

Can it retard the individual cylinder like j+s does?
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

I have tested the functionality where there is one IGT signal is retarded with the onset of Knock.
Last edited by HOODEY on Sun Nov 13, 2011 9:10 am, edited 1 time in total.
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Just added the code to the Toyota Interrupt subroutine.

Recieve one igt pulse and creates four corresponding to the cylinder currently firing.
Each of the outputs can be retarded depending on which cylinder is Knocking.

Stay tuned for demonstration using LEDs on the outputs.
hardtailer
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Re: Knock Detection with variable sensitivity over RPM

Post by hardtailer »

Impressive stuff, certainly on my list of must-have tuning tools.

Hoodye, you mentioned that some development work is required for configurations not yet covered and that this would involve active participation by the 'early' buyers, who would receive an updated chip for an additional fee and that later buyers would benefit from all this for free.
I would think that tackling it like this would leave many interested buyers on the fence and as such it could take a while before it all takes off.
How about offering the first 10 buyers the assembled kit for 125usd inc. The chip update for free. I think the experience gained from these 1st 10 will probably lead to a hardware update too, from which the 1st 10 wouldnt profit which I see as another reason to offer the first kits at a discount.
it's a proven method for GB's that need a minimum number of takers to get the product rolling.
Should 150usd be your lowest price, you could still consider this 'sales tactics' by announcing that after the initial batch is gone price will go up by x usd.

i for one can offer a BMW I4 16valve engine (s14b20 in an e30 320is) running ms2 (extra code 3.1.0), pcb 3 with edis as a development platform.
What do you reckon?
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Completed the Ignition sequence option long time ago.
Last edited by HOODEY on Sun Nov 13, 2011 9:11 am, edited 1 time in total.
hardtailer
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Re: Knock Detection with variable sensitivity over RPM

Post by hardtailer »

Ok, I understand. It was genuinely meant as food for thought. Nonetheless I am still interested but need to do some more reading up on it.

Re S14 OEM engine management: it originally runs on a Bosch Motronic system (M1.1 I believe) but it doesnt have a 60-2 trigger wheel. Instead it uses the 114 teeth on the starter ring gear and an extra tooth for TDC. These are sensed by 2 separate sensors.
AFM for engine load, IAT sensor inside AFM and a separate baro-sensor. TP-switch (idle and WOT), a CTS and NBO2-sensor finish the system off. No knock detection and a dizzy for spark distribution off a single coil.

Image
flywheel (extra tooth is just after 2 o'clock position in the picture)
Image
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

I believe this can be easily implemented (Similar to bosch 60-2) however as it is a very unusual setup work will not start until i have a committed $150 kit buyer.

The kit comes with a hundred page manual.

Alternatively you can go here for systems operating in Dumb Mode.

http://www.phormula.co.uk/KnockAnalyserPro.aspx

or here

http://www.google.com/products/catalog? ... D8Q8wIwAQ#


or here


http://finelineimports.net/index.php?ma ... cts_id=739

or here

http://www.trackdogracing.com/website/f ... _knock.htm
hardtailer
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Re: Knock Detection with variable sensitivity over RPM

Post by hardtailer »

Thanks for the reply.
I dont run the Bosch setup anymore (though it's still fitted to the car) but a 36-1 trigger wheel with a (Ford) VR sensor running EDIS wasted spark.
I understand for the windowing feature/individual knock detection I would require a cam sensor which I currently dont have but I dont mind to retard the ignition on all cylinders at the onset of knock for a start.
I sent you a PM re purchase.
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

I will code the 36-1 today. I have been studying this waveform over the weekend. Its like a diluted version of the bosch 60-2.

Is your vehicle 4 cyliner as there are 3 variants of the 36-1 dependent on the number of cylinders.

Without a cam input Ignition timing can still be determined.
Listening for knock between 10btdc and 40atdc can still be achieved.


However the monitor will only know if 1-4 fired or 3-2 fired. Not too bad at all :D
hardtailer
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Re: Knock Detection with variable sensitivity over RPM

Post by hardtailer »

money sent and email replied. Did you get my PM? I dont know how to get it out of my outbox...

It is indeed for the aforementioned 4 cylinder engine. The VR sensor is supposed to read tooth #9 (90 deg) after the missing tooth and cyl 1 at TDC (http://img.photobucket.com/albums/v668/ ... rwheel.jpg), but I put the trigger wheel wrong onto the crank pulley and as such the VR sensor reads #10 after the missing tooth with cyl. 1 at TDC.

With an appropriate offset in the Megasquirt it's not a problem but it would be handy if the KGL uses either the crank angle as MS calculates it or offers the provision in the GUI to define an offset too.

Keep up the good work!
jsmcortina
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Re: Knock Detection with variable sensitivity over RPM

Post by jsmcortina »

hardtailer wrote:money sent and email replied. Did you get my PM? I dont know how to get it out of my outbox...
PMs stay in your outbox until the recipient reads them.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
hardtailer
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Re: Knock Detection with variable sensitivity over RPM

Post by hardtailer »

thanks for the reply. I thought as much, when I saw that the PM had moved to 'sent' last night.
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

hardtailer will ship tomorrow.

jsmcortina can ms send out rpm and engine position information via the can bus?
jsmcortina
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Re: Knock Detection with variable sensitivity over RPM

Post by jsmcortina »

It will send you rpm if you ask for it. CAN is too slow for engine position. But it could be possible to output a knock window signal (on MS3 at least) you could use that directly as a window and infer rpm from it. (EDIT - on a hardware pin that is)

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

36-1 EDIS4 code finished will test tonight...
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

.
Last edited by HOODEY on Sun Nov 13, 2011 9:11 am, edited 1 time in total.
hardtailer
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Re: Knock Detection with variable sensitivity over RPM

Post by hardtailer »

package arrived safe and sound :D
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Let me know how everything goes. Drop me an email with any issues you may experience.
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Ford V8 added. 4.6l and 5.4l 36-1 trigger pattern.
Last edited by HOODEY on Sun Nov 13, 2011 9:12 am, edited 1 time in total.
HOODEY
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Re: Knock Detection with variable sensitivity over RPM

Post by HOODEY »

Knock Guard Lite in Standalone configuration. Labels and graphics need to be added.
Last edited by HOODEY on Sun Nov 13, 2011 9:13 am, edited 1 time in total.
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