what are you using for knock detection/control?
#1
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Just wondering what my options are for knock detection il be planning to use the megasquirt standalone ecu.
is there a self build guide for det cans?
i read something about using a microphone and something about using a bosch sensor instead is there a guide somewhere?
is there a self build guide for det cans?
i read something about using a microphone and something about using a bosch sensor instead is there a guide somewhere?
#2
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for hearing knock im using a home made det can... and for det controll im using a standalone ecu
but i dont know how well it all works cause i still have to get the car running lol... i had the det can on the motor when it ran and it works awesome! i could hear everything in the motor
i recomend everyone to build one... im planing on making a "how-to" vid and posing it on youtube but i dont know if i feel like it lol...
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#3
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For the lazy: I have 10 sets of electronic detcans sitting on my desk just waiting for final assembly (Now with battery holders and power buttons!!!). I'm also starting to a PNP knock input for MS1/2 with RPM based filtering ala TXS knocklite which will be taking priority as soon as I get my BMW finished up.
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From what I understand, if you can't program a sample period prior to ignition event, then there is no point in spending a cent on knock control. For this reason I run lots less spark angle than maximum and my car still runs with no issues.
#9
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J&S Ultra Safeguard
('cos I have stock ECU and base Powercard)
http://www.jandssafeguard.com/safeguard.html
('cos I have stock ECU and base Powercard)
http://www.jandssafeguard.com/safeguard.html
#10
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Det cans are king. If you run it through the ECU you must have frequency filtering and 2D noise filtering based on RPM in order to have any faith in it at all. Tune it conservative and fat, listen to the det cans, and check the plugs every 500 miles for pepper until you know it's not pinging. Set it up to pull timing in hot weather (high CLT/IAT).
#11
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J&S Ultra Safeguard
('cos I have stock ECU and base Powercard)
http://www.jandssafeguard.com/safeguard.html
('cos I have stock ECU and base Powercard)
http://www.jandssafeguard.com/safeguard.html
#12
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From http://www.jandssafeguard.com/tech.html
"Spark retard, within limits is the most powerful means of controlling detonation." and
"J&S Electronics has developed the SafeGuard which uses a knock sensor to provide feedback to it's microprocessor which, in turn, controls the timing for each cylinder on an individual, optimized basis." and
"the J&S SafeGurad can be set for up to 20 degrees of ignition retard."
Am I reading this wrong?
#13
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Not as fail as your reading comprehension
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Ignition yeah, but then that's a given surely
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OP I quite like the KnockLite from TurboXS, I've tried the KnockSense and as it has zero rpm sensitivity you either end up with no detection or a shitload of false knock (confirmed with electronic detcans). YMMV in this case, but I definately prefer the KL.
KL also has an output wich is pretty easy to plumb into a MegaSquirt, this will give you a rudimentary amount of automatic knock retard. You won't get any advanced windowing ect, but for the price and installation effort required, it's a nice to have as a failsafe when on track etc.
#16
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FWIW- My reading comprehension is fine. Perhaps the guy who spells like **** shouldn't lecture
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I stand corrected.
#20
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Here it is and works like a champ. I was able to detect the slightest knock, but nothing would have saved me from a oil pump failure, besides listening to others to remove the almuninum crank pulley.
http://autospeed.com/cms/A_0353/article.html
![](http://us1.webpublications.com.au/static/images/articles/i3/0353_8mg.jpg)
The picture above shows the unit from the website. The one that follows is the one I made with improvements.
- The wire coming from the alligator clamp is routed through the firewall and somewhere under the dash or glove compartment. The good thing about mine is it looks like a mp3 plug. The amplifier can be disconnected and stored, and the alligator clamp is strong enough to stay permanently on the engine bay or lets say for long periods of long time.
![](http://i93.photobucket.com/albums/l70/psiturbo/Mazda/DSC_4548.jpg)
The alligator clamp is connected on the electronic oil sensor. Try to place is far or out of the radiator fan airflow.
http://autospeed.com/cms/article.html?&A=0348
If you dont like reading, at least review the conclusion of the link above...
http://autospeed.com/cms/A_0353/article.html
![](http://us1.webpublications.com.au/static/images/articles/i3/0353_8mg.jpg)
The picture above shows the unit from the website. The one that follows is the one I made with improvements.
- The wire coming from the alligator clamp is routed through the firewall and somewhere under the dash or glove compartment. The good thing about mine is it looks like a mp3 plug. The amplifier can be disconnected and stored, and the alligator clamp is strong enough to stay permanently on the engine bay or lets say for long periods of long time.
![](http://i93.photobucket.com/albums/l70/psiturbo/Mazda/DSC_4548.jpg)
The alligator clamp is connected on the electronic oil sensor. Try to place is far or out of the radiator fan airflow.
http://autospeed.com/cms/article.html?&A=0348
If you dont like reading, at least review the conclusion of the link above...
Last edited by mazpr; 10-09-2010 at 05:25 AM.