NB OEM Knock Sensor Output - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 04-05-2009, 04:12 PM   #1
Junior Member
Thread Starter
iTrader: (9)
 
Join Date: Jan 2007
Posts: 455
Total Cats: 3
Default NB OEM Knock Sensor Output

I'm not hearing any knock but the knock sensor hit 104 (units?) on a boosted run. How does the sensor output correlate to damaging knock? Should the timing be retarded above a certain level?
Attached Thumbnails
NB OEM Knock Sensor Output-knock.png  
sv650_ck is offline   Reply With Quote
Old 04-05-2009, 04:37 PM   #2
Elite Member
iTrader: (46)
 
Stein's Avatar
 
Join Date: Dec 2007
Location: Nebraska
Posts: 4,812
Total Cats: 138
Default

I've seen some 100+ readings as well and have never heard any knock. Not sure what to make of it.

I tried to load a couple of my runs into Megalog Viewer and have been unsuccessful. What format do they have to be saved in? .csv?
Stein is offline   Reply With Quote
Old 04-05-2009, 04:58 PM   #3
Junior Member
Thread Starter
iTrader: (9)
 
Join Date: Jan 2007
Posts: 455
Total Cats: 3
Default

It should be in the .csv format but you have to remove the quotation marks from the header - See Turbo Roaches post below. I opened the file up with note pad and cut and paste TR's header and resaved.

https://www.miataturbo.net/forum/t33439/
sv650_ck is offline   Reply With Quote
Old 04-05-2009, 05:16 PM   #4
Elite Member
 
Join Date: Jul 2005
Posts: 6,454
Total Cats: 80
Default

The NB factory sensor output needs to be filtered to help the signal to noise ratio. I posted a schematic for such a filter in the ECu section.
JasonC SBB is offline   Reply With Quote
Old 04-05-2009, 11:09 PM   #5
Elite Member
iTrader: (15)
 
Join Date: Dec 2007
Location: San Antonio, Texas
Posts: 4,889
Total Cats: 28
Default

Here is a good thread on the Adaptronic forum:
Knock Logging...
Based on this thread the level you are seeing is about right. The Adaptronic has a programmable filter built-in which is what the thread is about.

Based on some use of electronic det cans, you can still have some light knocking that you will not be able to hear listening normally. So be careful.
ZX-Tex is offline   Reply With Quote
Old 04-06-2009, 03:23 AM   #6
Elite Member
 
Join Date: Jul 2005
Posts: 6,454
Total Cats: 80
Default

I glanced at that thread, and they dont seem to be talking about frequency filtering that I'm talking about.
JasonC SBB is offline   Reply With Quote
Old 04-06-2009, 08:39 AM   #7
Junior Member
Thread Starter
iTrader: (9)
 
Join Date: Jan 2007
Posts: 455
Total Cats: 3
Default

Quote:
Originally Posted by JasonC SBB View Post
The NB factory sensor output needs to be filtered to help the signal to noise ratio. I posted a schematic for such a filter in the ECu section.
Does it give you a line level output that you'd plug into an amp of some sorts?
sv650_ck is offline   Reply With Quote
Old 04-06-2009, 11:54 AM   #8
Elite Member
iTrader: (15)
 
Join Date: Dec 2007
Location: San Antonio, Texas
Posts: 4,889
Total Cats: 28
Default

No it is more like a microphone than a line output; it is a passive device. But it has enough power though to plug it into an amp.

Jason you are right as far as i can tell the Adaptronic setup is just a gain versus RPM filter, not a frequency filter.
ZX-Tex is offline   Reply With Quote
Old 04-08-2009, 06:54 PM   #9
Junior Member
Thread Starter
iTrader: (9)
 
Join Date: Jan 2007
Posts: 455
Total Cats: 3
Default

Quote:
Originally Posted by ZX-Tex View Post
Jason you are right as far as i can tell the Adaptronic setup is just a gain versus RPM filter, not a frequency filter.
I found this in the manual - appears there is filtering.
Attached Thumbnails
NB OEM Knock Sensor Output-knock.jpg  
sv650_ck is offline   Reply With Quote
Old 09-09-2009, 11:47 AM   #10
Elite Member
 
Join Date: Jul 2005
Posts: 6,454
Total Cats: 80
Default

FWIW the circuit I designed is more specific for the miata - it has a narrow bandpass filter tuned for the miata block's knock frequency. It also provides the power necessary to power the factory knock sensor. Its output voltage will be compatible with knock inputs designed for piezo sensors.
JasonC SBB is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Garrett Turbo, 1.8 Oil Pan, & Misc. Stuff nbdooey Miata parts for sale/trade 9 08-30-2017 10:50 PM
1994 Spec Miata Race Car SM/SM2/SSM For Sale Quinn Cars for sale/trade 6 10-23-2016 08:58 AM
My solution for Oiltemp and Oilpressure input into Megasuirt (MS3) Zaphod MEGAsquirt 41 01-24-2016 01:25 PM
MSPNPPro-MM0105: Coolant Temperature Output slomiata MEGAsquirt 5 10-07-2015 02:11 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 03:09 PM.