Air fuel ratio 02 sensors for data

General engine tech -- Drag Racing to Circle Track

Moderator: Team

carmakerevive
Member
Member
Posts: 53
Joined: Fri Apr 28, 2017 12:42 am
Location: NC/AU

Re: Air fuel ratio 02 sensors for data

Postby carmakerevive » Sun Sep 10, 2017 6:37 pm

^I've seen a few instances where a tuner has insisted on knock sensors, only to be unable to hear knock correctly when the engine is running also. or they've taken so long to identify the particular sound of pre-ignition that the length tune has blown out to weeks worth of labour.

And EGT's would be useful channel to log on a diesel engine, or perhaps a turbocharged one...but even then, i'd still prefer a wideband lambda anyday over an EGT channel...
"Poor planning on your part, does not constitute an emergency on mine..."

joe 90
Guru
Guru
Posts: 1879
Joined: Tue May 27, 2014 3:02 am
Location: The land of the long white cloud

Re: Air fuel ratio 02 sensors for data

Postby joe 90 » Mon Sep 11, 2017 1:08 am

Belgian1979 wrote:
I have got a question : if you can hear valvetrain noise outside of the engine bay, why wouldn't a knock sensor not hear that noise ? After all, it's a microphone attached to the engine.




There's 2 sorts of knock sensors, one is a microphone, the other isn't. It's more like an electronic tuning fork.
They work in completely different ways, most people have no clues?
The GM ones work best which are electronic tuning forks, They don't listen for a particular frequency, they detect the initial shock wave at zero Hz.
The microphone ones, all the published theory is completely wrong so they usually don't work.


An EGT sensor is pretty much standard equipment on a truck engine or industrial engine or even gas turbine.
A WB sensor isn't.
Need to think on that for a while.

Belgian1979
Guru
Guru
Posts: 3410
Joined: Sat Mar 26, 2011 10:34 am
Location: Belgium - Koersel

Re: Air fuel ratio 02 sensors for data

Postby Belgian1979 » Mon Sep 11, 2017 1:16 am

joe 90 wrote:
Belgian1979 wrote:
I have got a question : if you can hear valvetrain noise outside of the engine bay, why wouldn't a knock sensor not hear that noise ? After all, it's a microphone attached to the engine.




There's 2 sorts of knock sensors, one is a microphone, the other isn't. It's more like an electronic tuning fork.
They work in completely different ways, most people have no clues?
The GM ones work best which are electronic tuning forks, They don't listen for a particular frequency, they detect the initial shock wave at zero Hz.
The microphone ones, all the published theory is completely wrong so they usually don't work.


An EGT sensor is pretty much standard equipment on a truck engine or industrial engine or even gas turbine.
A WB sensor isn't.
Need to think on that for a while.


Both sensors you refer to are the same type. One of them however is tuned to a specific engine because they filter out other sound frequencies. That's it no more, no less.

Belgian1979
Guru
Guru
Posts: 3410
Joined: Sat Mar 26, 2011 10:34 am
Location: Belgium - Koersel

Re: Air fuel ratio 02 sensors for data

Postby Belgian1979 » Mon Sep 11, 2017 1:17 am

carmakerevive wrote:^I've seen a few instances where a tuner has insisted on knock sensors, only to be unable to hear knock correctly when the engine is running also. or they've taken so long to identify the particular sound of pre-ignition that the length tune has blown out to weeks worth of labour.

And EGT's would be useful channel to log on a diesel engine, or perhaps a turbocharged one...but even then, i'd still prefer a wideband lambda anyday over an EGT channel...


I found that knock sensors are better adapted at detecting valve train issues rather than distinguishing knock :D

joe 90
Guru
Guru
Posts: 1879
Joined: Tue May 27, 2014 3:02 am
Location: The land of the long white cloud

Re: Air fuel ratio 02 sensors for data

Postby joe 90 » Mon Sep 11, 2017 1:32 am

Belgian1979 wrote:Both sensors you refer to are the same type. One of them however is tuned to a specific engine because they filter out other sound frequencies. That's it no more, no less.



100% completely wrong.=fail.

Belgian1979 wrote:
carmakerevive wrote:^I've seen a few instances where a tuner has insisted on knock sensors, only to be unable to hear knock correctly when the engine is running also. or they've taken so long to identify the particular sound of pre-ignition that the length tune has blown out to weeks worth of labour.


I found that knock sensors are better adapted at detecting valve train issues rather than distinguishing knock :D


That's what happens when people don't know WTF they're doing.

Belgian1979
Guru
Guru
Posts: 3410
Joined: Sat Mar 26, 2011 10:34 am
Location: Belgium - Koersel

Re: Air fuel ratio 02 sensors for data

Postby Belgian1979 » Mon Sep 11, 2017 4:05 am

joe 90 wrote:
Belgian1979 wrote:Both sensors you refer to are the same type. One of them however is tuned to a specific engine because they filter out other sound frequencies. That's it no more, no less.



100% completely wrong.=fail.

Belgian1979 wrote:
carmakerevive wrote:^I've seen a few instances where a tuner has insisted on knock sensors, only to be unable to hear knock correctly when the engine is running also. or they've taken so long to identify the particular sound of pre-ignition that the length tune has blown out to weeks worth of labour.


I found that knock sensors are better adapted at detecting valve train issues rather than distinguishing knock :D


That's what happens when people don't know WTF they're doing.


Over the time that I've been a member and have seen you comment, I have seen more wrong things written by you than correct things. Others have already demonstrated that more than once.

redliner
Expert
Expert
Posts: 571
Joined: Sun Feb 26, 2012 4:07 pm

Re: Air fuel ratio 02 sensors for data

Postby redliner » Mon Sep 11, 2017 4:50 am

Warp Speed wrote:
hoodeng wrote:One feature of EGT when used in conjunction with O2 is when ,O2 is stable and there is a rise in EGT could indicate on the system i used, timing being later than ideal, and if the EGT was less than our target would indicate advanced timing from ideal , of course other factors were to be taken into account as data is holistic so a negative impact on ET with all other parameters in scope would narrow down an area to be investigated.If you do go down the data logging route ,first up you will be swamped with a sea of lines that will make you go quiet for a while ,,but it will make sense once sorted.
If you can ,source your system from a supplier that gives backup ..When we had trouble in the early days of a new bike ,the guys that supported that data logging brand were also running a vehicle at similar meetings so i was extremely lucky to have these guys a few pits away.
All data is singular vehicle relevant pretty much as guys that run multiple vehicles know ,what worked on one does not necessarily mean another vehicle of the same type would respond exactly the same with the same interpretations.

Bit like weather stations , yours might not be 'Bureau of Meteorology' correct but if it is consistent it will be observations relevant to your vehicle ,,,, i could never work out what people were looking for when they compared weather stations????

All that said , data monitoring and recording your exhaust to start with is a mighty big step in the right direction just by itself!!!

Cheers,


How do you come up with an EGT target temp?

EXACTLY!!!!!

joe 90
Guru
Guru
Posts: 1879
Joined: Tue May 27, 2014 3:02 am
Location: The land of the long white cloud

Re: Air fuel ratio 02 sensors for data

Postby joe 90 » Mon Sep 11, 2017 5:03 am

redliner wrote:
Warp Speed wrote:How do you come up with an EGT target temp?

EXACTLY!!!!!


Through testing and tuning.

EGT is always hottest at a lambda of 1.
No excess of air and no excess of fuel,it's all being used.
It's cooler when lean and it's cooler when rich.

As to how hot, it depends on the engine, fuel type, RPM and load.
Full throttle is hotter than part throttle, peak torque RPM is hotter than higher or lower RPM.

That's all when the timing is tuned correctly.
Less timing advance will be hotter, more timing advance = broken.
That's what the knock sensor is for.


How about piston engined aircraft?

WB 02 or EGT?

https://aviation.stackexchange.com/ques ... ch-or-lean

digger
Expert
Expert
Posts: 903
Joined: Sun Jan 27, 2008 6:39 am

Re: Air fuel ratio 02 sensors for data

Postby digger » Mon Sep 11, 2017 6:15 am

Depends on your priorities. Last time checked it's not one or the other generally speaking

Warp Speed
Guru
Guru
Posts: 2000
Joined: Wed Jun 25, 2008 12:46 pm
Location: NC

Re: Air fuel ratio 02 sensors for data

Postby Warp Speed » Mon Sep 11, 2017 6:40 am

joe 90 wrote:
redliner wrote:
Warp Speed wrote:How do you come up with an EGT target temp?

EXACTLY!!!!!


Through testing and tuning.

EGT is always hottest at a lambda of 1.
No excess of air and no excess of fuel,it's all being used.
It's cooler when lean and it's cooler when rich.

As to how hot, it depends on the engine, fuel type, RPM and load.
Full throttle is hotter than part throttle, peak torque RPM is hotter than higher or lower RPM.

That's all when the timing is tuned correctly.
Less timing advance will be hotter, more timing advance = broken.
That's what the knock sensor is for.


How about piston engined aircraft?

WB 02 or EGT?

https://aviation.stackexchange.com/ques ... ch-or-lean


Aircraft use EGTs to keep the engine safe, not for maximum performance!

In-Tech
Guru
Guru
Posts: 1484
Joined: Wed Apr 21, 2010 3:35 am

Re: Air fuel ratio 02 sensors for data

Postby In-Tech » Mon Sep 11, 2017 7:17 am

As noted a few times in this thread, EGT is worth monitoring but is not the "end all" tuning guage. 8 WBo2's and 8 egt's will teach you some things. Doing CARB certification we will have the cylinders within a 1/4 AFR and EGT all over the place...hmm, why is that? It's because one cylinder will have more mass flow than another depending on rpm and load(ya know, pulses in the manifold). This also drastically changes with a bigger cam/overlap and also why OEM's generally have little overlap. That little overlap and late IVC event sure comes into play doesn't it? =D>
Heat is energy, energy is horsepower...but you gotta control the heat.
-Carl

Firedome8
Expert
Expert
Posts: 854
Joined: Wed Sep 21, 2016 5:16 pm

Re: Air fuel ratio 02 sensors for data

Postby Firedome8 » Mon Sep 11, 2017 7:28 am

does pre ignition knock ?

Belgian1979
Guru
Guru
Posts: 3410
Joined: Sat Mar 26, 2011 10:34 am
Location: Belgium - Koersel

Re: Air fuel ratio 02 sensors for data

Postby Belgian1979 » Mon Sep 11, 2017 8:48 am

In-Tech wrote:As noted a few times in this thread, EGT is worth monitoring but is not the "end all" tuning guage. 8 WBo2's and 8 egt's will teach you some things. Doing CARB certification we will have the cylinders within a 1/4 AFR and EGT all over the place...hmm, why is that? It's because one cylinder will have more mass flow than another depending on rpm and load(ya know, pulses in the manifold). This also drastically changes with a bigger cam/overlap and also why OEM's generally have little overlap. That little overlap and late IVC event sure comes into play doesn't it? =D>


correct. Fully agree.

Belgian1979
Guru
Guru
Posts: 3410
Joined: Sat Mar 26, 2011 10:34 am
Location: Belgium - Koersel

Re: Air fuel ratio 02 sensors for data

Postby Belgian1979 » Mon Sep 11, 2017 8:49 am

Firedome8 wrote:does pre ignition knock ?


No, but it sure does heat up things and that could lead to...:lol:

The Radius Kid
Expert
Expert
Posts: 625
Joined: Mon May 28, 2012 5:46 pm

Re: Air fuel ratio 02 sensors for data

Postby The Radius Kid » Mon Sep 11, 2017 10:18 am

You guys are still weird.
The Nazis didn't lose WWII,they just changed uniforms.Now they run the place.


Return to “Engine Tech”

Who is online

Users browsing this forum: 70MC, 77cruiser, Brian M, EngineNut, Google [Bot], greenhj, Harleyboy14, harold, Heinz1, hpetew, jasonn, jimjamm65, RevTheory and 45 guests