NefMoto

Technical => Tuning => Topic started by: NOTORIOUS VR on April 06, 2013, 07:40:54 AM



Title: Knock ears/det cans
Post by: NOTORIOUS VR on April 06, 2013, 07:40:54 AM
I'm thinking of setting up a group guy as an introduction to these knock ears: http://gizzmousa.com/knock-monitor.html

Seems like a great piece, not sure how many people here tune outside of Motronic, but if you do have a good set of det cans like this can really help with the big HP stuff.

Just wanted to gauge some interest. :)


Title: Re: Knock ears/det cans
Post by: Jason on April 06, 2013, 08:54:13 AM
You should be able to do this much cheaper...  Many OEM's do in vehicle tuning using a plain old Shure 58 microphone, as well as some rally teams.


Title: Re: Knock ears/det cans
Post by: NOTORIOUS VR on April 06, 2013, 09:25:56 AM
You should be able to do this much cheaper...  Many OEM's do in vehicle tuning using a plain old Shure 58 microphone, as well as some rally teams.

I already have a set of det cans, but they're without a filter..

This being adjustable and with DSP processing, plus the logging software is really nice... not to mention 2 analog outputs for datalogging.

It's not really comparable to a basic device you're talking about.


Title: Re: Knock ears/det cans
Post by: silentbob on April 07, 2013, 12:57:46 AM
...  Many OEM's do in vehicle tuning using a plain old Shure 58 microphone....

What. Who for example?


Title: Re: Knock ears/det cans
Post by: prj on April 07, 2013, 08:13:44 AM
OEM's do knock tuning with in-cylinder pressure transducers.

What. Who for example?

Look who's back. Have a look at the 5000mbar megathread :)


Title: Re: Knock ears/det cans
Post by: Jason on April 07, 2013, 08:43:33 AM
OEM's do knock tuning with in-cylinder pressure transducers.

Engine dyno mapping, sure.  However I know of one OEM that does in-car tuning with the mic because the pressure transducers are too fragile for in-vehicle work.  They also do ALL of their borderline work with the mic.

Think low volume "ultra" performance variants of an existing high performance vehicle already in production.


Title: Re: Knock ears/det cans
Post by: silentbob on April 07, 2013, 11:22:14 AM
Engine dyno mapping, sure.  However I know of one OEM that does in-car tuning with the mic because the pressure transducers are too fragile for in-vehicle work.  They also do ALL of their borderline work with the mic.

Think low volume "ultra" performance variants of an existing high performance vehicle already in production.
Don't know what the americans do but I have never seen anything like this here. Typical knock recognition calibration is done on an engine dyno and in the car only the base noise level is checked or fine adjusted. Therefore you have mobile indication systems with especially prepared cylinder heads or pressure sensing spark plugs. You don't even necessarily need an extra position sensor because you can use the 60-2 wheel.

Can't imagine this works in OEM quality standards especially on noisy supercharged applications


Title: Re: Knock ears/det cans
Post by: silentbob on April 07, 2013, 11:25:06 AM
Look who's back. Have a look at the 5000mbar megathread :)

I'll have a look. Hopefully I'll have some more time for this stuff the upcoming month  :(


Title: Re: Knock ears/det cans
Post by: NOTORIOUS VR on April 07, 2013, 08:08:17 PM

Can't imagine this works in OEM quality standards especially on noisy supercharged applications

If you are writing off det cans as a whole, that is a mistake.  The human brain is a great detector of knock.

I currently use a simple unfiltered electronic det can set that uses a Bosch knock sensor and it works quite well. 

The unit I've linked to takes that a step further and allows you to tailor the units built in filters and gain control to help with noisy engines/environments. The datalogging and other features are only a bonus IMO and a "nice to have" when you simply don't have the means to have OEM level knock detection setups like in-cyl sensors, etc.

Again, this is not generally for people that mainly use OEM ECU's like ME7 etc that have dialed in knock systems.  This is more geared to aftermarket ECU tuning, etc.


Title: Re: Knock ears/det cans
Post by: silentbob on April 07, 2013, 10:02:32 PM
If you are writing off det cans as a whole, that is a mistake.  The human brain is a great detector of knock.

I currently use a simple unfiltered electronic det can set that uses a Bosch knock sensor and it works quite well. 

The unit I've linked to takes that a step further and allows you to tailor the units built in filters and gain control to help with noisy engines/environments. The datalogging and other features are only a bonus IMO and a "nice to have" when you simply don't have the means to have OEM level knock detection setups like in-cyl sensors, etc.

Again, this is not generally for people that mainly use OEM ECU's like ME7 etc that have dialed in knock systems.  This is more geared to aftermarket ECU tuning, etc.
I totally understand and I don't have experiance with such devices.
The thing that makes me wonder is that it is used on OEM applications where you have precise definitions from hardware construction which pressure peaks are considered knock and which not ( like described in the FR). "Knock"you can hear doesn't necessarily mean that it is knock that is considered "dangerous" and makes the ECU adjust ignition.


Title: Re: Knock ears/det cans
Post by: NOTORIOUS VR on April 08, 2013, 05:39:24 AM
I totally understand and I don't have experiance with such devices.
The thing that makes me wonder is that it is used on OEM applications where you have precise definitions from hardware construction which pressure peaks are considered knock and which not ( like described in the FR). "Knock"you can hear doesn't necessarily mean that it is knock that is considered "dangerous" and makes the ECU adjust ignition.

Ah well yes that I do not know, in OEM applications I wouldn't think they use anything like this as claimed above.  That said, now a days I'd be surprised if they don't just model everything in a computer completely skipping the cylinder pressure sensors completely for the most part.  Or I'm guessing soon that day will come.



Title: Re: Knock ears/det cans
Post by: jibberjive on April 08, 2013, 06:55:47 AM
I think it's going the opposite direction, that in-cylinder pressure transducers are slowly going to become the norm, even for aftermarket tuners, as technology advances and scales up.  Kinda like how now the Borg Warner EFR turbo chargers have provisions for relatively affordable turbo RPM sensors, when they used to be a pretty exotic feature in the past.  How cool would it be if eventually the 'knock sensor' on your average normal production car is permanently integrated pressure transducers for each cylinder.


Title: Re: Knock ears/det cans
Post by: jaymemaurice on April 08, 2013, 06:59:28 PM
How cool would it be if eventually the 'knock sensor' on your average normal production car is permanently integrated pressure transducers for each cylinder.

IMHO that coolness will depend on if the CEL turns on and fails the E-Test when that transducer fails and if I end up having to buy $70 spark plugs.
Would be cool though if each cylinders metering, spark, and fuel delivery was controlled completely independently.


Title: Re: Knock ears/det cans
Post by: Acki on April 09, 2013, 05:21:26 AM
Don't know what the americans do but I have never seen anything like this here. Typical knock recognition calibration is done on an engine dyno and in the car only the base noise level is checked or fine adjusted. Therefore you have mobile indication systems with especially prepared cylinder heads or pressure sensing spark plugs. You don't even necessarily need an extra position sensor because you can use the 60-2 wheel.

Can't imagine this works in OEM quality standards especially on noisy supercharged applications

Word. In this way it's done. ;)


Title: Re: Knock ears/det cans
Post by: NOTORIOUS VR on April 09, 2013, 07:06:32 AM
I think it's going the opposite direction, that in-cylinder pressure transducers are slowly going to become the norm, even for aftermarket tuners, as technology advances and scales up.  Kinda like how now the Borg Warner EFR turbo chargers have provisions for relatively affordable turbo RPM sensors, when they used to be a pretty exotic feature in the past.  How cool would it be if eventually the 'knock sensor' on your average normal production car is permanently integrated pressure transducers for each cylinder.

I think we would see Ion Sensing ignition systems in mass production long before pressure sensors considering there are production cars that have Ion sensing.


Title: Re: Knock ears/det cans
Post by: fredrik_a on April 09, 2013, 07:24:59 AM
I think we would see Ion Sensing ignition systems in mass production long before pressure sensors considering there are production cars that have Ion sensing.

I'ts been used in Saab cars since the 90-is...


Title: Re: Knock ears/det cans
Post by: NOTORIOUS VR on April 09, 2013, 07:36:06 AM
I'ts been used in Saab cars since the 90-is...

Are you sure they still use it?

I thought it was only one model in the 90's... 900 turbo I think?  With the CDI "cassette" ignition box?


Title: Re: Knock ears/det cans
Post by: fredrik_a on April 09, 2013, 07:43:30 AM
Are you sure they still use it?

I thought it was only one model in the 90's... 900 turbo I think?  With the CDI "cassette" ignition box?


Still use it? Saab went out of business last year.
It was used in Trionic 5 and Trionic 7 (Saab 900, 9-3 old generation and 9-5 for instance).
Trionic 8 (9-3 new generation) didn't use it and for the turbo charged 2.8 litre V6 engine they
used Bosch Me9.


Title: Re: Knock ears/det cans
Post by: Acki on April 09, 2013, 08:36:01 AM
The 2.8 V6T is a GM High Feature V6 Holden engine. Also used in Vectra/Insignia (different chain system, older and newer stage of the engine).


Title: Re: Knock ears/det cans
Post by: NOTORIOUS VR on April 09, 2013, 09:41:48 AM

Still use it? Saab went out of business last year.
It was used in Trionic 5 and Trionic 7 (Saab 900, 9-3 old generation and 9-5 for instance).
Trionic 8 (9-3 new generation) didn't use it and for the turbo charged 2.8 litre V6 engine they
used Bosch Me9.

I understand that, your post made it seem like they continued to use it for their newer generation cars that's all.

Not sure if BMW still uses it, but ion sense was used in their V10 engines.


Title: Re: Knock ears/det cans
Post by: fredrik_a on April 09, 2013, 11:47:11 AM
your post made it seem like they continued to use it for their newer generation cars that's all.

Ah, sorry about that. They kept it though almost until the bitter end as the 9-5 series using T7 was manufactured until 2009/2010.
Tuning for Saab cars is found at http://trionic.mobixs.eu/