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Old 03-13-2012, 10:04 PM   #1
Evil Twin Rob
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Let's talk EGT's

First off, I have legitimate questions and curiosity about EGT's, and I would like to see knowledgeable responses, not a bunch of vendor/member bashing. Let's keep it civil.

Would monitoring the EGT's on S/C or turbo applications have an advantage? Where would the best place be to put sensors?
Are multiple sensors better than a single sensor?
Can these sensors be used as a failsafe to pull timing and/or boost?
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Old 03-13-2012, 11:02 PM   #2
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[QUOTE]Would monitoring the EGT's on S/C or turbo applications have an advantage? Where would the best place be to put sensors?
Are multiple sensors better than a single sensor?
Can these sensors be used as a failsafe to pull timing and/or boost?[/QUOTE]

1) yes, it gives you more information & can be used as an additional failsafe
2) generally the closer to the combustion chamber, the better
3) Yes, more sensors provide more information (to a point). You could better detect issues with individual cylinders or trim fuel per cylinder to account for uneven manifold distribution.
4) On most systems Yes, although in some cases pulling timing will increase egt's

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Old 03-13-2012, 11:08 PM   #3
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Originally Posted by SPDu4ea View Post
Quote:
Would monitoring the EGT's on S/C or turbo applications have an advantage? Where would the best place be to put sensors?
Are multiple sensors better than a single sensor?
Can these sensors be used as a failsafe to pull timing and/or boost?
1) yes, it gives you more information & can be used as an additional failsafe
2) generally the closer to the combustion chamber, the better
3) Yes, more sensors provide more information (to a point). You could better detect issues with individual cylinders or trim fuel per cylinder to account for uneven manifold distribution.
4) On most systems Yes, although in some cases pulling timing will increase egt's
A better failsafe would be to just cut the spark for that cylinder and cool it with fuel
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Old 03-13-2012, 11:11 PM   #4
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The only useful info you're going to get is if you have one per cylinder right at the exhaust port. Then if you can tweak by cylinder and even them all out, you could run a hair more timing or identify a manifold that's not flowing even or something else that's causing one cylinder to run hotter.

You're not going to see much use from it that your other gauges won't already alert you to on a SC car.
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Old 03-14-2012, 05:47 PM   #5
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EGT Thread

OK, I asked Marcus if he minded if we talk about EGT in the thread HE started and he said to start a NEW one on that topic(EGT's). That is 100% within his rights. I am glad I asked since I surely did not want to cause him any more undue stress. I apologize for the guys who continued to post on that matter. I am sure they must have missed his response.

I PM'd a member here to please comment on a post he made. It is all up to him if he even wants to or not. I found the post to be extremely interesting. It is exactly what I have been talking about. Engine data right down to each individual cylinder. The post takes it even further and addressed engine MANAGEMENT using data from each cylinder. This is exactly what I need to hear much more about. Is anyone else interested??

There is a lot more than PROEFI and AEM out there. It cant hurt to at least listen and learn more about them.

Quote:
Originally Posted by 02PRUV View Post
LOL I have 6 egt's and an ECU that can also subtract timing and add fuel etc by egt heat
The above statement is so cool it makes the hairs on my arm stand up. Sorry, but it does. The forum is open.
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Old 03-14-2012, 07:15 PM   #6
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Ok Dave asked me to put up some more info here. Well here is my 2 cents. AEM as an ECU is pretty rubbish. Don't try and tell me otherwise I have tried one. Software is nice and has everything. Hardware is a joke. I have used $1000 Aussie ecu's that we pick on as rubbish that have better hardware. And to be honest I have found that with most aftermarket American designed ECU's. Especially for the money you spend on them. The only reason AEM and Proefi are used so much in by people on this forum is the install is cheap. Plug in harness is very nice. But that's where it ends. Look if you have the money and time the only real way to do it is a Motec. But to be honest I couldn't afford the $11,000 in ECU and software only. If people didn't keep bagging out Mert so much there would of been a lot of knowledge being shared using the best ECU in the world on an S54. Then there is Autronic, again a great ECU but the guys there don't really want to spend the time configuring new pickups and I spent a bit of time trying to set up an S54 with them and I lost interest cause they didn't put the time into it. Then you have Vipec, great ecu. Has lots of inputs and outputs, can control all the devices on new cars like cams, FBW throttle, cruise control, alarm system inputs etc and has been used extensively through Australia, Europe and America on BMW's and they have all the BMW crank/cam pickups programmed into their software already. They also have multiple O2 inputs, egt inputs, knock sensor inputs etc.

Now setting up a knock sensor map is highly time consuming and very hard. If you want knock sensing on a motec the only way they do it is they will come and set it up for you at a starting cost of $8000. I believe that OEM knock sensing or motec setting it up is probably the only way to go to get it right with knock sensing. Even though Vipec have a map for it and I have the knock sensors connected I haven't tried to program it. I got told that you can tune the engine, make sure it's not knocking then measure the noise on the knock sensors and add 10%. It sounded a bit crude to me and I never did it. That said I have also been told by many tuners that if an engine is tuned correctly you don't need knock sensing.

Then you have EGT's. Vipec is great with inputs and has a drop down list for selecting a list of sensors already setup which include EGT sensors. I like EGT's because engines do change cylinder to cylinder and if you can get them running closer you will most of the time make more power safer. Things are never accurate. Injectors, intake runners exhaust etc. All this will change how a cylinder is operating. The only way you can see this is EGT's on each exhaust runner no more than 1 inch away from the port. I have even put bungs in each runner on the intake and we hook up a boost gauge to each intake runner to make sure boost in each runner is the same. So we measure differences in and out of the cylinder. This might sound extreme but it's the only way to be sure.

There are other things with what companies in the US are doing I'd be scared of with BMW's cause BMW do some different stuff. Controlling cams with the factory ECU is one. At the end of the day you don't know what the DME is going to do with the cams if it sees or doesn't see something that it should be. That's a variable that I'd want to remove from the car if I couldn't control it. Then there is the fuel pump. If the DME is controlling the fuel pump it adjusts voltage to the fuel pump. Therefore fuel pressure will vary outside of your control or knowledge for when it does it. If you still use the DME to control the fuel pump you need the DME to turn on a relay and connect the power through the relay to the pump straight from the battery (don't forget a fuse).

These are all things I have played with on my BMW. I have had 4 different ECU's in it. I have found issues and fixed a couple. I'm no expert but I did build this thing with my own two hands and I have made the mistakes myself and learnt the hard way. No warranty for me.
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Old 03-14-2012, 07:46 PM   #7
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Originally Posted by Bdave View Post
OK, I asked Marcus if he minded if we talk about EGT in the thread HE started and he said to start a NEW one on that topic(EGT's). That is 100% within his rights. I am glad I asked since I surely did not want to cause him any more undue stress. I apologize for the guys who continued to post on that matter. I am sure they must have missed his response.

I PM'd a member here to please comment on a post he made. It is all up to him if he even wants to or not. I found the post to be extremely interesting. It is exactly what I have been talking about. Engine data right down to each individual cylinder. The post takes it even further and addressed engine MANAGEMENT using data from each cylinder. This is exactly what I need to hear much more about. Is anyone else interested??

There is a lot more than PROEFI and AEM out there. It cant hurt to at least listen and learn more about them.



The above statement is so cool it makes the hairs on my arm stand up. Sorry, but it does. The forum is open.
Do you realize that when you pull timing, your EGT's rise faster than when you pull fuel??? so this feedback loop is COMPLETELY counter productive, and effectively continue pulling timing and adding fuel. This isn't a 'theory' it's a fact. The factories use this procedure for heating up catalytic converters....and it works VERY well. Ever hear an E60 M5 start up cold? That is why they sound so off.
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Old 03-14-2012, 08:11 PM   #8
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Originally Posted by 02PRUV View Post
Ok Dave asked me to put up some more info here. Well here is my 2 cents. AEM as an ECU is pretty rubbish. Don't try and tell me otherwise I have tried one. Software is nice and has everything. Hardware is a joke. I have used $1000 Aussie ecu's that we pick on as rubbish that have better hardware. And to be honest I have found that with most aftermarket American designed ECU's. Especially for the money you spend on them. The only reason AEM and Proefi are used so much in by people on this forum is the install is cheap. Plug in harness is very nice. But that's where it ends. Look if you have the money and time the only real way to do it is a Motec. But to be honest I couldn't afford the $11,000 in ECU and software only. If people didn't keep bagging out Mert so much there would of been a lot of knowledge being shared using the best ECU in the world on an S54. Then there is Autronic, again a great ECU but the guys there don't really want to spend the time configuring new pickups and I spent a bit of time trying to set up an S54 with them and I lost interest cause they didn't put the time into it. Then you have Vipec, great ecu. Has lots of inputs and outputs, can control all the devices on new cars like cams, FBW throttle, cruise control, alarm system inputs etc and has been used extensively through Australia, Europe and America on BMW's and they have all the BMW crank/cam pickups programmed into their software already. They also have multiple O2 inputs, egt inputs, knock sensor inputs etc.

Now setting up a knock sensor map is highly time consuming and very hard. If you want knock sensing on a motec the only way they do it is they will come and set it up for you at a starting cost of $8000. I believe that OEM knock sensing or motec setting it up is probably the only way to go to get it right with knock sensing. Even though Vipec have a map for it and I have the knock sensors connected I haven't tried to program it. I got told that you can tune the engine, make sure it's not knocking then measure the noise on the knock sensors and add 10%. It sounded a bit crude to me and I never did it. That said I have also been told by many tuners that if an engine is tuned correctly you don't need knock sensing.

Then you have EGT's. Vipec is great with inputs and has a drop down list for selecting a list of sensors already setup which include EGT sensors. I like EGT's because engines do change cylinder to cylinder and if you can get them running closer you will most of the time make more power safer. Things are never accurate. Injectors, intake runners exhaust etc. All this will change how a cylinder is operating. The only way you can see this is EGT's on each exhaust runner no more than 1 inch away from the port. I have even put bungs in each runner on the intake and we hook up a boost gauge to each intake runner to make sure boost in each runner is the same. So we measure differences in and out of the cylinder. This might sound extreme but it's the only way to be sure.

There are other things with what companies in the US are doing I'd be scared of with BMW's cause BMW do some different stuff. Controlling cams with the factory ECU is one. At the end of the day you don't know what the DME is going to do with the cams if it sees or doesn't see something that it should be. That's a variable that I'd want to remove from the car if I couldn't control it. Then there is the fuel pump. If the DME is controlling the fuel pump it adjusts voltage to the fuel pump. Therefore fuel pressure will vary outside of your control or knowledge for when it does it. If you still use the DME to control the fuel pump you need the DME to turn on a relay and connect the power through the relay to the pump straight from the battery (don't forget a fuse).

These are all things I have played with on my BMW. I have had 4 different ECU's in it. I have found issues and fixed a couple. I'm no expert but I did build this thing with my own two hands and I have made the mistakes myself and learnt the hard way. No warranty for me.
Thanks so much. But now I feel the need for a pump controller thread. You really should never try and control a pump via voltage alone AFAIK. Isnt it very hard on the electric motor? It will burn out quick.
AFAIK, the best way is via some sort of "pulse modulation" or wave technology?... Like the Aeromotive fuel pump controller we got?

"Avoid any device that reduces voltage to your fuel pump. Low voltage will destroy a 12V DC motor. The Aeromotive FPSC does not reduce voltage! The FPSC emits a pulse modulation signal that is harmless to the pumpís motor."

http://aeromotiveinc.com/products-pa...ed-controller/


Back on topic. I just cant swing a whole new ECU at this point. I did have my builder buy 6 EGT probes and our port guy has drilled and tapped the manifold. I HOPE to hell he is not more than an inch away from the port. IDK. I was going to leave them in for tuning and then revert to my single probe at the collector and matching gauge. Now, I am not so sure.
I dont have any way (yet) of displaying the 6 gauges in my car. They were supposed to be for tuning and or diagnostic purposes only. Advice?

I cant at this point make the probes actually control anything. But I am very good at monitoring things. I could at least have glance at them when the car is stressed most on the track. I admit, the ideal set up is to have them function as active probes. Some day...
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Old 03-14-2012, 08:17 PM   #9
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Quote:
Originally Posted by Jason@proefi View Post
Do you realize that when you pull timing, your EGT's rise faster than when you pull fuel??? so this feedback loop is COMPLETELY counter productive, and effectively continue pulling timing and adding fuel. This isn't a 'theory' it's a fact. The factories use this procedure for heating up catalytic converters....and it works VERY well. Ever hear an E60 M5 start up cold? That is why they sound so off.

I think Jason was addressing some one else's post. This one:
Originally Posted by 02PRUV View Post
LOL I have 6 egt's and an ECU that can also subtract timing and add fuel etc by egt heat.

I cant respond to Jason's questions. Would 02PRUV care to please?

I was going to leave all the tuning decisions up to my tuner for what I have going on. I simply supplied 6 EGT's so he had data to work with. I dont even have an active EGT system, nor immediate plans to have one. I am interested in learning about them.
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Old 03-14-2012, 08:37 PM   #10
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Originally Posted by 02PRUV View Post
Ok Dave asked me to put up some more info here. Well here is my 2 cents.

<snip/>

Then you have EGT's. Vipec is great with inputs and has a drop down list for selecting a list of sensors already setup which include EGT sensors. I like EGT's because engines do change cylinder to cylinder and if you can get them running closer you will most of the time make more power safer. Things are never accurate. Injectors, intake runners exhaust etc. All this will change how a cylinder is operating. The only way you can see this is EGT's on each exhaust runner no more than 1 inch away from the port. I have even put bungs in each runner on the intake and we hook up a boost gauge to each intake runner to make sure boost in each runner is the same. So we measure differences in and out of the cylinder. This might sound extreme but it's the only way to be sure.

There are other things with what companies in the US are doing I'd be scared of with BMW's cause BMW do some different stuff. Controlling cams with the factory ECU is one. At the end of the day you don't know what the DME is going to do with the cams if it sees or doesn't see something that it should be. That's a variable that I'd want to remove from the car if I couldn't control it. Then there is the fuel pump. If the DME is controlling the fuel pump it adjusts voltage to the fuel pump. Therefore fuel pressure will vary outside of your control or knowledge for when it does it. If you still use the DME to control the fuel pump you need the DME to turn on a relay and connect the power through the relay to the pump straight from the battery (don't forget a fuse).

These are all things I have played with on my BMW. I have had 4 different ECU's in it. I have found issues and fixed a couple. I'm no expert but I did build this thing with my own two hands and I have made the mistakes myself and learnt the hard way. No warranty for me.


I have an EGT question that maybe you or another poster here may be able to answer. Is there much variance in the temperature during the 720ļ of the combustion cycle as the sensor may measure 1" from a cylinder port?

I would guess the temperature would be at it's peak just after the valves open and exhaust gases are flowing. Would these temperature variances warrant timed measurements. Maybe 90 to 180 degrees delay from the ignition timing?
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Old 03-15-2012, 07:37 AM   #11
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Originally Posted by Jason@proefi View Post
Do you realize that when you pull timing, your EGT's rise faster than when you pull fuel??? so this feedback loop is COMPLETELY counter productive, and effectively continue pulling timing and adding fuel. This isn't a 'theory' it's a fact. The factories use this procedure for heating up catalytic converters....and it works VERY well. Ever hear an E60 M5 start up cold? That is why they sound so off.
I wasn't stating what I do with them I was stating what can be done with a Vipec. If you want more specifics the ECU is capable of adding/subtracting fuel and/or timing via EGT. I'm sure you know what a Vipec is capable of though

Instead of trying to make me look bad like you do to Chris you could actually explain to people what causes higher EGT's and why more fuel doesn't work and why EGT's go higher when adding more fuel on a turbo car. And what the difference is with doing this turbo compared to N/A. But I forgot your here to sell a product not be part of an online community.
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Old 03-15-2012, 11:08 AM   #12
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I wasn't stating what I do with them I was stating what can be done with a Vipec. If you want more specifics the ECU is capable of adding/subtracting fuel and/or timing via EGT. I'm sure you know what a Vipec is capable of though

Instead of trying to make me look bad like you do to Chris you could actually explain to people what causes higher EGT's and why more fuel doesn't work and why EGT's go higher when adding more fuel on a turbo car. And what the difference is with doing this turbo compared to N/A. But I forgot your here to sell a product not be part of an online community.
I'm not trying to make ANYONE look bad. Simply correcting a misconception. The problem with having infinite flexability on some ecu's is that the user can get an idea in their head, and actually try something that will cause damage. Yes, I could explain how all of that works, but you made the comment, so why didn't you do it? You certainly had some reason for making that statement in the first place...right? What was your train of thought?
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Old 03-15-2012, 12:57 PM   #13
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Originally Posted by 02PRUV View Post
I wasn't stating what I do with them I was stating what can be done with a Vipec. If you want more specifics the ECU is capable of adding/subtracting fuel and/or timing via EGT. I'm sure you know what a Vipec is capable of though

Instead of trying to make me look bad like you do to Chris you could actually explain to people what causes higher EGT's and why more fuel doesn't work and why EGT's go higher when adding more fuel on a turbo car. And what the difference is with doing this turbo compared to N/A. But I forgot your here to sell a product not be part of an online community.
atleast he didn't say it was proprietary...
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Old 03-15-2012, 02:01 PM   #14
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Lets talk about how log exhaust manifolds increase the exhaust gas temps
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Old 03-15-2012, 02:23 PM   #15
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There are several things that affect exhaust temperature... Exhaust back pressure, late ignition timing, lean mixtures, valve over lap, fuel type, compression, distance from the exhaust valve...to name a few. You ABSOLUTELY cannot use EGT's for a tuning device...other than cylinder trims, and even then...you have to use good judgement, as fuel mixture is not always the cause of differences between the probes. Coolant flow and air flow play a big part. Individual EGT's give you a piece of the puzzle...but you have to understand how to put those pieces together. I wouldn't recommend individual EGT's to someon who doesn't understand the pitfalls of using them.
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Old 03-15-2012, 02:59 PM   #16
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Lets talk about how log exhaust manifolds increase the exhaust gas temps
Not only log manifolds cause unequal EGT's, unequal length tubular headers can do the same.
I cannot find the information I posted a long time ago. It pertained to having very much elevated EGTs in two of the four cylinders of a boxer motor (ie Subaru)when using unequal length headers. Which will result in premature engine failure.

For Cliff notes, skip the rest and just read the last paragraph of this post. You have been warned. Reader at his own risk.

So, how can a tuner help equalize hotter than normal temps when using log or unequal length tubular headers. Would running a COLDER spark plug in any of the offending cylinders be of ANY help? I am not asking if it would totally cure the issue, just help lower higher EGT;s in maybe one or two cylinders that are running unduly hot due to exhaust manifold design.

Jason mentioned multiple other reasons for increased and or unequal EGT's. How are you even going to know you have issues unless you bother to measure them? OK, fine about the values not being able to play and ACTIVE roll in tuning. What about a passive role? Its pure data left to a tuner to decide how to approach the situation.


What else can help equalize our EGT's? Not all of us are prepared to go out and have a ghastly expensive custom equal length tubular header fabricated.

My thoughts are to try to get all 6 EGT's running on an established baseline(preferably on a Mustang Dyno or other type that can add a significant load) . Jason was the one I think that brought up this very important point of tuning on something other than a Dyno Jet. I agree.

Once a baseline has been established with as close matching EGT;s as possible....it was my thought that simply reporting a much higher than normal EGT in any one cylinder to your tuner would be a prudent course of action. Leave it to the tuner to decide what should or should not be done.

Isnt it possible that had Marcus's car had 6 EGT probes in even a passive role that some sort of fore warning might have occurred? I am throwing this out there. I do not know the answer.

...or even cylinder head temperature probes and gauges?
I do know that there is a large selection of four probe EGT kits available for motorcycles. Why not a highly boosted and stressed six cylinder car motors?

Look. The bottom line is that there may lots of cars out there that seem to be running perfectly normal. In the mean time one single cylinder, for what ever reason. is being toasted towards premature failure. I for one would never feel comfortable with a build unless I had each and every cylinder EGT measured...at least in the build and tuning phase!
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Old 03-15-2012, 03:08 PM   #17
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Not only log manifolds cause unequal EGT's, unequal length tubular headers can do the same.
I cannot find the information I posted a long time ago. It pertained to having very much elevated EGTs in two of the four cylinders of a boxer motor (ie Subaru)when using unequal length headers. Which will result in premature engine failure.

So, how can a tuner help equalize hotter than normal temps when using log or unequal length tubular headers. Would running a COLDER spark plug in any of the offending cylinders be of ANY help? I am not asking if it would totally cure the issue, just help lower higher EGT;s in maybe one or two cylinders that are running unduly hot due to exhaust manifold design.

What else can help EQUALIZE our EGT's? Not all of us are prepared to go out and have a ghastly expensive custom equal length tubular header fabricated.

My thoughts are to try to get all 6 EGT's running on an established baseline(preferably on a Mustang Dyno or other type that can add a significant load) . Jason was the one I think that brought up this very important point of tuning on something other than a Dyno Jet. I agree.

Once a baseline has been established with as close matching EGT;s as possible....it was my thought that simply reporting a much higher than normal EGT in any one cylinder to your tuner would be a prudent course of action. Leave it to the tuner to decide what should or should not be done.

Isnt it possible that had Marcus's car had 6 EGT probes in even a passive role that some sort of fore warning might have occurred? I am throwing this out there. I do not know the answer.

...or even cylinder head temperature probes and gauges?
I do know that there is a large selection of four probe EGT kits available for motorcycles. Why not a highly boosted and stressed six cylinder car motors?
Tuning on a Dynojet with a load cell (like mine) is fine. When tuning on loaded dyno's you have to understand what your doing...I.E. don't put the engine in an unrealistic environment..(I.E. don't park it at 4krpm and full boost and start tuning, as you will NEVER see those conditions, and your tune is different for an accelerating engine).

First, determine if your EGT differential is ACTUALLY a problem. You will never get them IDENTICAL anyway. The probes themselves have a tolerance of +/- 25c (depending on which ones you use...it could be higher). Changing the plug temperature won't change your EGT's but if your backpressure is high enough to maintain temperature inside the cylinder, might be a preventative resolution. Again...there are a lot of variables, so if you desire to do this the RIGHT way, find someone with experience doing so.
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Old 03-15-2012, 04:48 PM   #18
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Originally Posted by Jason@proefi View Post
Tuning on a Dynojet with a load cell (like mine) is fine. When tuning on loaded dyno's you have to understand what your doing...I.E. don't put the engine in an unrealistic environment..(I.E. don't park it at 4krpm and full boost and start tuning, as you will NEVER see those conditions, and your tune is different for an accelerating engine).

First, determine if your EGT differential is ACTUALLY a problem. You will never get them IDENTICAL anyway. The probes themselves have a tolerance of +/- 25c (depending on which ones you use...it could be higher). Changing the plug temperature won't change your EGT's but if your backpressure is high enough to maintain temperature inside the cylinder, might be a preventative resolution. Again...there are a lot of variables, so if you desire to do this the RIGHT way, find someone with experience doing so.
OK, great. Thank you. Of course, I am not so naive to think the values can be made identical. I am mostly concerned I dont have any cylinders showing excessive EGT. A single probe at the header would be a poor way to try to discover that situation. Just one cylinder running too hot may not be enough to really show once its traveled and merged with 5 other values at the header junction.

So, you think it is impossible to use EGT data to function in an active roll with some ECU on the market?....or simply counter productive. Does not matter to me so much at this point. Currently, all I want to do is provide my tuner data that he can use as he see fit. Good to know Dyno jet can be loaded (with care) to aid in such tuning.

I just have this very strong feeling that all the trouble we are going to will bear fruit. Hey, maybe everything right from the start will all be with in tolerances. At least I will have a base line to monitor. If I see one cylinder start to go crazy on EGT, it could save a world of hurt by taking the time to investigate.

Could a significantly dangerous elevated EGT reading in a single cylinder be used as a fail safe by reducing boost and throwing a code? It would not be really involved with tuning the car, but rather preventing any immediate damage. A real person would be brought in to interpret the whys and where fores.

EGT is just one among many different measurements that we can take. IMO, I think it prudent to add this to the list.

Jason, what are your thoughts on cylinder head temperature data? Useful or not useful? One over all probe or six probes? Is is related to EGT directly or indirectly?

I wont be any where near my car when it is being tuned. I do have a man who is is extremely experienced with our boosted E46's and all the parameters that go with it. Evidently he is quite pleased I chose to spend the extra time and $$ to have my mani fitted for six identical EGT probes.
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Old 03-15-2012, 11:49 PM   #19
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There are several things that affect exhaust temperature... Exhaust back pressure, late ignition timing, lean mixtures, valve over lap, fuel type, compression, distance from the exhaust valve...to name a few. You ABSOLUTELY cannot use EGT's for a tuning device...other than cylinder trims, and even then...you have to use good judgement, as fuel mixture is not always the cause of differences between the probes. Coolant flow and air flow play a big part. Individual EGT's give you a piece of the puzzle...but you have to understand how to put those pieces together. I wouldn't recommend individual EGT's to someon who doesn't understand the pitfalls of using them.
This is a confusing thing to say, because I see no use for a laymen to have an egt probe 5 feet down their exhaust.
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Old 03-16-2012, 12:24 AM   #20
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This is a confusing thing to say, because I see no use for a laymen to have an egt probe 5 feet down their exhaust.
Like with most aftermarket gauges, a layman may not fully understand the importance of the numbers, but he should still be able to spot an abnormal reading & investigate the cause.

edit: not 5 feet down the exhaust though lol

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