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My exhuast gas temperature meter along with 2 thermocouples came in this weekend. The thermocouples are nice stainless units with 1/4 inch pipe thread that screw into bungs welded into the header tubes.
I have 2 probes and the meter reads and hold both displays.
I intend to try this unit and if I like it buy another one.
I will pull the passenger header tomorrow and weld in 4 bungs. One in each tube as close to the header flange as convenient.
I will plug 2 of the bungs with dry seals and run 2 thermocouples. After I get a pattern of those you cylinders I will move the thermocouples to the other 2 c:thud: ylinders and compare the running temperatures.
If I like the unit I will buy a second one and do the same to the drivers side.
In that case I would monitor 4 cylinders at all times with the ability to move the thermocouples to the other 4 cylinders at random.
I am looking for temperatures in the 1320-1350 range with 1420-1450 being dangerous.
A motor that detonates has sharp temperature spikes as high as 1600F.
It will be another interesting tuning tool.
Along with the LM-1 wide band oxygen sensor I should be able to dial this thing in
 

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Discussion Starter #3
There must be something out there that lets you monitor all eight at a time.
I would still need to buy 8 screw in thermocouples and the ones I bought are over $50 each . I would just need a switch, a switch that had 8 channels and I would then be able to switch between the various cylinders.
The meter itself was about $250.
 

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I would still need to buy 8 screw in thermocouples and the ones I bought are over $50 each . I would just need a switch, a switch that had 8 channels and I would then be able to switch between the various cylinders.
The meter itself was about $250.
Sorry Norvall, WRONG.

I was involved with process controls in industry for many years.So, let's explain my comment.

More than likely, your thermocouples are type K. This is chromel/alumel. In other words, the two conductors are dissimlar metals in contact. Take note. This dissimalarity MUST be maintained from source to meter input. Connectors, extension wire, and even switches for thermocouples are made from these same alloys. $$$ You cannot solder, crimp, or use common switches anywhere in the system, as it will HUGELY affect accuracy.
A meter with multiple inputs is your best bet. If you want to switch between inputs, you have to obtain the proper means. I suggest you obtain a catalogue from OMEGA process controls. They will have all that you need.
PM me for any clarification you may require. Jeff IBEW, 28 years.
 

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:agree: I was going to say something like that also (without all the in depth tech stuff LOL ), that's why you never cut the wire on the sensor, you always leave it the length it came. A buddy of mine cut the wire on the one he used to tune his go kart, it was reading completely incorrectly after he did that and the only fix is buying a new sensor.

You can get a multi switch from autometer to monitor multiple EGTs on one gauge.

Didn't champion have thermocoupler plugs many years ago? They used them on race cars, never heard anything about it for a long time. That would be the easiest way to monitor EGTs per cyl.
 

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Discussion Starter #7
Sorry Norvall, WRONG.

I was involved with process controls in industry for many years.So, let's explain my comment.

More than likely, your thermocouples are type K. This is chromel/alumel. In other words, the two conductors are dissimlar metals in contact. Take note. This dissimalarity MUST be maintained from source to meter input. Connectors, extension wire, and even switches for thermocouples are made from these same alloys. $$$ You cannot solder, crimp, or use common switches anywhere in the system, as it will HUGELY affect accuracy.
A meter with multiple inputs is your best bet. If you want to switch between inputs, you have to obtain the proper means. I suggest you obtain a catalogue from OMEGA process controls. They will have all that you need.
PM me for any clarification you may require. Jeff IBEW, 28 years.
Guys I spent 40 years in research at a leading enginering university. I have worked with thermocouples all those years. My meter came from Omega as did the thermocouples with 8 foot stainless leads. I have switches in the lab that would handle 8 thermocouples, you just rotate the dial to get which thermocouple you want to read. I also have bulk wire if I wanted to make my own thermocouples but they are not as nice as the bought ones.
Yes I am using a K type thermocouple. I also have a spot welder for making thermocouples plus a number of reference sources to check their accuracy.
I will not go the switch route. I want to order another 2 channel meter and 2 more thermocouples and run 2 on the left and 2 on the right and change their cylinder location from time to time to check all cylinders.
All my thermocouples use the correct yellow male plugs and red is always always negative on any thermocouple.
The K type is good for 2500 degrees and forms a perfect 45 degree slope on a milivolt output vs temp chart. That is why it is the most accurate and popular of the thermocouples.
 

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Discussion Starter #8
http://www.pegasusautoracing.com/productdetails.asp?RecId=64

http://www.pegasusautoracing.com/productdetails.asp?RecId=67



try this, it`s the one in my car...they also make a dual gauge. Westach and Autometer are brothers.....
...redvetracr
Thanks redvetracr I have seen both the gage and the thermocouples before but wanted something that was digital readout and very accurate. I deal with thermocouples meters and calibration all the time so setting up a system is not really hard for me. My meter also stored the peak readings on 2 channels so I can run and check the peak temperatures after a run.
 

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Guys I spent 40 years in research at a leading enginering university. I have worked with thermocouples all those years. My meter came from Omega as did the thermocouples with 8 foot stainless leads. I have switches in the lab that would handle 8 thermocouples, you just rotate the dial to get which thermocouple you want to read. I also have bulk wire if I wanted to make my own thermocouples but they are not as nice as the bought ones.
Yes I am using a K type thermocouple. I also have a spot welder for making thermocouples plus a number of reference sources to check their accuracy.
I will not go the switch route. I want to order another 2 channel meter and 2 more thermocouples and run 2 on the left and 2 on the right and change their cylinder location from time to time to check all cylinders.
All my thermocouples use the correct yellow male plugs and red is always always negative on any thermocouple.
The K type is good for 2500 degrees and forms a perfect 45 degree slope on a milivolt output vs temp chart. That is why it is the most accurate and popular of the thermocouples.
:rolling: I guess I have been told. Glad to hear you are savvey with the nuances of the system.:rolling: I really did not mean to be crass, just informative, and make sure you were aware.:thud:
I guess the only thing I can add for those reading is that one conductor is always magnetic, +, while the negative is not. :D
 

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Discussion Starter #10
:rolling: I guess I have been told. Glad to hear you are savvey with the nuances of the system.:rolling: I really did not mean to be crass, just informative, and make sure you were aware.:thud:
I guess the only thing I can add for those reading is that one conductor is always magnetic, +, while the negative is not. :D
big2bird this is an information post. I don't need help and guys like you and I are just informing others about what is involved. Marck is also a very informed guy and all comments are welcome.
Now again this post is more for educating others on what's involved and cost. I intend to post pictures of the welded in bungs, the thermocouples installed as well as the dry seals closing off the unused ports.
All informative information is welcome and your comments are something I missed , I know about them but others might not.
So yes add all you can to any of my posts. They are to educate.

Thanks for adding to my post.
 

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I know about them but others might not.
So yes add all you can to any of my posts.

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Well, I for one sure don't :laughing: At least now I have some idea of how you did it and what not to do if I want to duplicate what you've done.

I intend to post pictures of the welded in bungs, the thermocouples installed as well as the dry seals closing off the unused ports.

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Keep it coming Norval. I'm particularly looking forward to the results. I'm very interested in the peak temps that will come from this and the distribution. Do you expect significant variations from one cylinder to another?
 

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I tuned Yamaha 2 stroke racing MC's and Go-Karts with a switched type K TC for years with good results. The Fluke#12 Meter has a type K TC capability and they respond quite well.
 

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alright, here's a question that came up at work today but I didn't bother asking it...

In my limited thermocouple experience, the terminals on the meters are both copper. I assume this is a standard situation that the meter automatically compensates for when you select which type of thermocouple you're using. Otherwise you'd have to have different terminals for every type of thermocouple you wanted to read.

Thus, does it matter which lead you connect to which terminal? I would expect not.

Am I off track on all this? Is the copper terminal thing something they just tell us in class to help us wrap our minds around the concepts?

TIA
 

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Discussion Starter #14
alright, here's a question that came up at work today but I didn't bother asking it...

In my limited thermocouple experience, the terminals on the meters are both copper. I assume this is a standard situation that the meter automatically compensates for when you select which type of thermocouple you're using. Otherwise you'd have to have different terminals for every type of thermocouple you wanted to read.

Thus, does it matter which lead you connect to which terminal? I would expect not.

Am I off track on all this? Is the copper terminal thing something they just tell us in class to help us wrap our minds around the concepts?

TIA
Our meters have two different female plugs. One is wider then the other or another way is one is small and one is big. You can NOT put the plug in the wrong way.
We then select a yellow male end that is marked positive + and negative -
The RED wire always always is negative so you put the red wire on the negative terminal on the special plug and you put the other wire on the plus + terminal.
Now when you plug into the meter you automatically have the right wire in the right hole
You can also get GREEN extension wire that you can extend a thermocouple but it is easier to just order whatever length lead you want right from Omega.
I will post pictures on the completed setup Thursday. I welded the 4 bungs into the passenger header tonight and will work on it tomorrow with a camera and show how it is done.
Thursday:thumbsup:
 

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Our meters have two different female plugs. One is wider then the other or another way is one is small and one is big. You can NOT put the plug in the wrong way.
We then select a yellow male end that is marked positive + and negative -
The RED wire always always is negative so you put the red wire on the negative terminal on the special plug and you put the other wire on the plus + terminal.
Now when you plug into the meter you automatically have the right wire in the right hole
You can also get GREEN extension wire that you can extend a thermocouple but it is easier to just order whatever length lead you want right from Omega.
I will post pictures on the completed setup Thursday. I welded the 4 bungs into the passenger header tonight and will work on it tomorrow with a camera and show how it is done.
Thursday:thumbsup:
so if you use the same meter with a type J and a type K, do you use different sets of female terminals? We mostly use type J and have similar plugs from omega with different size male terminals and little engravings of IR for iron and CO for constantan.

Thanks for the info, and I look forward to the pics. Next I'll probably be bugging you about exactly what you can tell from the exhaust temps...
 

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so if you use the same meter with a type J and a type K, do you use different sets of female terminals? We mostly use type J and have similar plugs from omega with different size male terminals and little engravings of IR for iron and CO for constantan.

Thanks for the info, and I look forward to the pics. Next I'll probably be bugging you about exactly what you can tell from the exhaust temps...
:laughing: I had to check up on my reading, since I have not done this crap in awhile. Norvalls GREEN extension comment spurred this . Last time I installed this material, K extension was YELLOW, now I see Yellow is ANSI standard, and Green Is IEC standard.:crazy:
To answer your terminal question, somewhere the circuit must change from input generator to display circuitry. The input terminals could be copper at the final destination as long as behind it is the termination circuitry. (It has to change somewhere). I see the I/O boards are now bipolar and unipolar, so I ASSUME your teachings are correct for the equipment you are utilising.
 

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You guys could check with "Mr. Blue66".
He's got a blown BB and I think sensors on all eight headers if I remember correctly. He's had them for a few years, so should know his way around them for that application.
 

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Discussion Starter #18
so if you use the same meter with a type J and a type K, do you use different sets of female terminals? We mostly use type J and have similar plugs from omega with different size male terminals and little engravings of IR for iron and CO for constantan.

Thanks for the info, and I look forward to the pics. Next I'll probably be bugging you about exactly what you can tell from the exhaust temps...
The J type thermocouple has a upper limit of 1550 and the slope of the line on a graph is not quite as good. You are looking for a 45 degree slope on the graph showing temperature VS milli volt output. This gives the most definition of a voltage change VS temp.
The J is just a little steeper then 45 while the K is about the best slope and goes to 2500.
When you get the little yellow end plugs they are male and on the plug is a letter designating the type of thermocouple. I will take a picture of this plug also and post it with my writeup tomorrow.
The meter take all different thermocouples and I use alot of platanum ones as well. My upper limit is the lab for a furnace is 4532 F or 2500C. That is hot:thumbsup:
 

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You guys could check with "Mr. Blue66".
He's got a blown BB and I think sensors on all eight headers if I remember correctly. He's had them for a few years, so should know his way around them for that application.
I have seen lots of race cars with 8 probes and 8 meters all in a row. I intend to run 4 thermocouples and 2 meters for tuning but in the end I after I am happy everything will come out and the bungs will just carry dry plugs.
Each bung is taped so when a dry seal is installed it bottoms at the same time the bottom of the plug is flush with the inside of the header tube to cut down on turbulance.
Again I will post pictures of this tomorrow.
 
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