[charlie66]

Has any one ever use these? And what are they really for?

http://www.westach.com/gauge_images/712-4WK.jpg

[wrongway]

They were a factory item with a gauge on a late '70s Arctic Cat free air snowmobile that I had. Pretty common back then for monitoring head temps on air cooled snowmobiles. They replaced the washer under the spark plug.

[charlie66]

Oh so there not something that would be used on a car.. I was thinking it might have something to do with an other way of measuring egts .. Lol . I guess when I think of it now that makes no sense ..

Thanks..

[BruceWilkie]

They are also used on aircraft. I used them on snowmobile motors to monitor head temps along with egt gauges. They're useful but EGT gauge with fast response (stinger) probes from ExhaustGasTechnology are best. Westach gauges hold up well btw.

[charlie66]

Originally Posted by BruceWilkie

They are also used on aircraft. I used them on snowmobile motors to monitor head temps along with egt gauges. They're useful but EGT gauge with fast response (stinger) probes from ExhaustGasTechnology are best. Westach gauges hold up well btw.

If someone just used these instead of the egt gages would you be able to at least tell what cylinder was the hottest?

[Jack Gifford]

Are those Westach thermocouples quite expensive?
The thermocouples I used in industry were comprised of a platinum/platinum-rhodium junction- extremely precious metals.

[charlie66]

Originally Posted by Jack Gifford

Are those Westach thermocouples quite expensive?
The thermocouples I used in industry were comprised of a platinum/platinum-rhodium junction- extremely precious metals.

Not really Jack Click on - products and then -accessories- then -Cht thermocouples - then Under -sparkplug ring type- and see for your self http://www.westach.com/

[Torment]

Originally Posted by charlie66

If someone just used these instead of the egt gages would you be able to at least tell what cylinder was the hottest?

Actually can be a better indicator of combustion temps than EGT. EGT and combustion temps are inversely related for any given power level...

[Torment]

Issue is because they have more mass they're going to be slower to respond in a drag racing type application. In steady state (aircraft) or step testing they provide good feedback.

[BruceWilkie]

Originally Posted by Jack Gifford

Are those Westach thermocouples quite expensive?
The thermocouples I used in industry were comprised of a platinum/platinum-rhodium junction- extremely precious metals.

Westach lists the 14mm spark plug ring type with 4ft lead at $31.84 each. Patch cables are priced based on length. 18" is $8.88 and the longest they list(15') is $18.72.

Westach... http://www.westach.com/ click on products then click on accessories to find thermocouples and patch cables

pic of spark plug type thermocouple




http://www.westach.com/gauge_images/202-SS-SS.jpg
Patch cable (2ft)

[Torment]

You can make one yourself with a copper washer... Super cheap! lol

[BruceWilkie]

This is the EGT probe type I prefer. Its a quick response type. If you are recording data this can detect a single misfire at 8000 rpm. My pair were still working after 10 years(seasons) of use/abuse. (even with several burn-downs over those years)

http://www.exhaustgas.com/ProductDet...pID=&BasketID=

CHT gauges do tell the temp the plug is seeing at the head interface. On a Pontiac its probably going to show the center plugs a bit hotter than the outers. MAYBE at extreme boost levels the temp difference is enough to MAYBE warrant cooler plugs in the center than needed for the outers???

Air cooled motors these and oil temp gauges are as important as water temp gauges.

BTW Westach does sell selector switches (various configurations) so one gauge can monitor whatever probe you want to keep track of.

[charlie66]

Originally Posted by Torment

Actually can be a better indicator of combustion temps than EGT. EGT and combustion temps are inversely related for any given power level...

Right now it would be easier to not use the probs in my primaries because there always moving around and loosening up . Being you replace them with plug washers , do they go on and off the plug easy? or are they a pain like the stock plugs washers are after using...

Thanks for your input on this...

[charlie66]

Does any one know if these plug thermocouples
will work with this unit? Here's a link...

http://www.altronicsinc.com/egt-syst...ecorder-1.html

[Torment]

Originally Posted by charlie66

Right now it would be easier to not use the probs in my primaries because there always moving around and loosening up . Being you replace them with plug washers , do they go on and off the plug easy? or are they a pain like the stock plugs washers are after using...

Thanks for your input on this...

They can be installed and removed from the plugs with no difficulty.

[Torment]

Originally Posted by charlie66

Does any one know if these plug thermocouples
will work with this unit? Here's a link...

http://www.altronicsinc.com/egt-syst...ecorder-1.html

I'm not directly familiar with the Altronics unit, but a type K thermocouple is a type K thermocouple - so I wouldn't think you would have an issue with the signal. You would want to insure the plug in end (not spark plug end) is the right connector though. I'd likely just call Altronics to confirm.

Looking at the image it appears they're wiring 4 thermocouples to on 'plug' and another 4 to the other 'plug' - based on the image. So... if that is correct, you'd simply wire the spark plug thermocouples in the same fashion. Each thermocouple has 2 wires - the red one is actually the negative, not the positive.

Hope this helps.

[charlie66]

Originally Posted by Torment

I'm not directly familiar with the Altronics unit, but a type K thermocouple is a type K thermocouple - so I wouldn't think you would have an issue with the signal. You would want to insure the plug in end (not spark plug end) is the right connector though. I'd likely just call Altronics to confirm.

Looking at the image it appears they're wiring 4 thermocouples to on 'plug' and another 4 to the other 'plug' - based on the image. So... if that is correct, you'd simply wire the spark plug thermocouples in the same fashion. Each thermocouple has 2 wires - the red one is actually the negative, not the positive.

Hope this helps.

That end I will just splice it in.

Not sure what you mean by wiring 4 to 1 plug. With my probs there are 2 wires per prob and they run to a lug block and that's it you're done. I was thinking the same wiring for the plug thermocouplers no ?

[Torment]

Yes the same wiring - 2 wires per probe. I was just referring to the picture of the Altronics unit you linked where they show the thermocouples that come with it, my assumption being you want to substitute spark plug thermcouples.

[charlie66]

Originally Posted by Torment

Yes the same wiring - 2 wires per probe. I was just referring to the picture of the Altronics unit you linked where they show the thermocouples that come with it, my assumption being you want to substitute spark plug thermcouples.

Yes, now I see what you are talking about. I only have half of that because I only needed enough for 4 cylinders. So Im not use to seeing both sides . lol..

Guess ill be calling Altronics to see how compatible they are...


Thanks