Air fuel ratio 02 sensors for data
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Re: Air fuel ratio 02 sensors for data
If anyone is interested I have a good little used Innovate LM12 for sale, can log up to 12 wideband AFR and log other things like oil pressure, rpm, etc.
Re: Air fuel ratio 02 sensors for data
EGTs are also a safety limit, specially with an expensive industrial engine. The actual temp depends on the engine and the fuel. Typically up at 600 deg C you'll see a 20 or so deg C variance between cylinders and maybe 150 deg across the turbo.Warp Speed wrote:And again, what are EGTs good for?
Certainly not much relating to this thread! LOL
If you let the EGTs get too high while tuning, then you might end up melting something.
A WB can't help you in that respect.
More tools are always better than less tools.
A WB, like a NB tells you rich or lean.
Not how hot.
Won't tell you if it's pre igniting and won't tell you if it's knocking.
Re: Air fuel ratio 02 sensors for data
Would the EGT drop if the cylinder goes into Pre ignition?
A good test is worth a thousand opinions.
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Re: Air fuel ratio 02 sensors for data
With regard to engine temperatures, there are four possibilities.Firedome8 wrote:Would the EGT drop if the cylinder goes into Pre ignition?
Piston temp goes up, EGT goes up
Piston temp goes up, EGT goes down.
Piston temp goes down, EGT goes down.
Piston temp goes down, EGT goes up.
Each will result from some combination of tuning or operating conditions.
Re: Air fuel ratio 02 sensors for data
There are two courses of discussion occurring here, one is from the engine builder and in house dyno sector the other is from the track sector, both have very relevant and important inputs here, but coming back to ALKYBURNERS question ,he was looking for track relevant ,specifically drag racing data acquisition ,and that is EGT in conjunction with AFR being the most suitable first step of de mystifying his tune and performance.
I personally have little experience with dyno cell operation but with track experience i could dig myself out of a hole so to speak , no problem, and there are a multitude of guys out there that would make me look novice!
the validity of track data logging to this day is an irreplaceable tool .
If the trace of AFR is irregular but the EGT will nearly follow an overlay line from previous good passes[in our case] ,if it doesn't ,start looking there will be a reason,if you have stable EGT and a higher or lower AFR and the ET is off ,alter the fuel delivery to suit.If data is irregular, find out why and rectify ,throwing your arms up in the air publicly and ditching the technology will attract a very interested crowd,,,your category's competitors.
Dave is right in my opinion, Good data is king!!
A long long time ago i was told at the track that if we "Tip the can and bump the mag the ET"S will be in the bag" probably the worst piece of advice given in confidence, if only it was that simple there would be no need for data acquisition.
Cheers.
I personally have little experience with dyno cell operation but with track experience i could dig myself out of a hole so to speak , no problem, and there are a multitude of guys out there that would make me look novice!
the validity of track data logging to this day is an irreplaceable tool .
If the trace of AFR is irregular but the EGT will nearly follow an overlay line from previous good passes[in our case] ,if it doesn't ,start looking there will be a reason,if you have stable EGT and a higher or lower AFR and the ET is off ,alter the fuel delivery to suit.If data is irregular, find out why and rectify ,throwing your arms up in the air publicly and ditching the technology will attract a very interested crowd,,,your category's competitors.
Dave is right in my opinion, Good data is king!!
A long long time ago i was told at the track that if we "Tip the can and bump the mag the ET"S will be in the bag" probably the worst piece of advice given in confidence, if only it was that simple there would be no need for data acquisition.
Cheers.
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Re: Air fuel ratio 02 sensors for data
perhaps you can elaborate on wgi
Perhaps you can elaborate on what conditions cause each scenario?David Redszus wrote:With regard to engine temperatures, there are four possibilities.Firedome8 wrote:Would the EGT drop if the cylinder goes into Pre ignition?
Piston temp goes up, EGT goes up
Piston temp goes up, EGT goes down.
Piston temp goes down, EGT goes down.
Piston temp goes down, EGT goes up.
Each will result from some combination of tuning or operating conditions.
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Re: Air fuel ratio 02 sensors for data
I don't see how EGT would be able to predict pre-ignition, but maybe I can learn something.
Like I said, I think EGT's combined with WB could probably tell you more about variances in ignition timing and let you detect misfires, but I don't see more use for EGT's further than that. On the cost aspect I'm not sure it would bring additional value.
Like I said, I think EGT's combined with WB could probably tell you more about variances in ignition timing and let you detect misfires, but I don't see more use for EGT's further than that. On the cost aspect I'm not sure it would bring additional value.
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Re: Air fuel ratio 02 sensors for data
I think you'll find that if you correlate the two together(O2/EGT),you predict disaster before it happens.Belgian1979 wrote:I don't see how EGT would be able to predict pre-ignition, but maybe I can learn something.
Like I said, I think EGT's combined with WB could probably tell you more about variances in ignition timing and let you detect misfires, but I don't see more use for EGT's further than that. On the cost aspect I'm not sure it would bring additional value.
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Re: Air fuel ratio 02 sensors for data
Coupled with a knock sensor which works.
As opposed to one which doesn't.
As opposed to one which doesn't.
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Re: Air fuel ratio 02 sensors for data
Unfortunately, with most any solid roller performance engine, there is so much engine noise, that a knock sensor becomes useless!joe 90 wrote:Coupled with a knock sensor which works.
As opposed to one which doesn't.
Re: Air fuel ratio 02 sensors for data
Hi, do you have much experience with GM's knock control strategies? I don't have a ton of experience with EFI and solid rollers but one comes to mind that worked very well. It was a pair of ~1500hp blown 571 BBC's for a boat. I spent about 3 days on the dyno just on knock control. Using a crank/cam sensors and 8 coils(sequential spark), the GM strategy allows you to listen at a programmable time before and after TDC on the compression/combustion stroke for each cylinder and ignores all other noise outside that window of time. It will also only retard the cylinder that is knocking instead of all of them at a whack.Warp Speed wrote:Unfortunately, with most any solid roller performance engine, there is so much engine noise, that a knock sensor becomes useless!joe 90 wrote:Coupled with a knock sensor which works.
As opposed to one which doesn't.
I think I have a "data "screen shot of this somewhere, I'll post it when I find it.
Heat is energy, energy is horsepower...but you gotta control the heat.
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Re: Air fuel ratio 02 sensors for data
Just speculating, but preignition is in some ways similar to advancing the spark timing and so would likely result in an unexpected drop in EGTs, probably not simultaneously in all cylinders.Belgian1979 wrote:I don't see how EGT would be able to predict pre-ignition, but maybe I can learn something.
Like I said, I think EGT's combined with WB could probably tell you more about variances in ignition timing and let you detect misfires, but I don't see more use for EGT's further than that. On the cost aspect I'm not sure it would bring additional value.
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Re: Air fuel ratio 02 sensors for data
I've got a solid roller engine and a knock sensor but it's a japper.
It doesn't make much noise.
If you've got one and it DOES make lots of noise....it's built wrong.
It doesn't make much noise.
If you've got one and it DOES make lots of noise....it's built wrong.
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Re: Air fuel ratio 02 sensors for data
That's a possibility Bill, like I said I never used EGT's so don't have much to add. I used O2's extensively though.MadBill wrote:Just speculating, but preignition is in some ways similar to advancing the spark timing and so would likely result in an unexpected drop in EGTs, probably not simultaneously in all cylinders.Belgian1979 wrote:I don't see how EGT would be able to predict pre-ignition, but maybe I can learn something.
Like I said, I think EGT's combined with WB could probably tell you more about variances in ignition timing and let you detect misfires, but I don't see more use for EGT's further than that. On the cost aspect I'm not sure it would bring additional value.
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Re: Air fuel ratio 02 sensors for data
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.joe 90 wrote:I've got a solid roller engine and a knock sensor but it's a japper.
It doesn't make much noise.
If you've got one and it DOES make lots of noise....it's built wrong.