# EGT/Pyrometer Probe placement?



## benzivr6 (Feb 16, 2001)

Hi I have a question for you guy who use EGT gauges on your cars. Were would be the most acurrate placement for a EGT/Pyrometer probe on your exhaust manifold? do you guys run it close to the cylinder # 1 or just let it collect dead center to all the exhaust ports? If it helps I am also using a ATP cast style VR6 manifold. Thanks in advance guys


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## kevhayward (Mar 13, 2007)

Mine is in the middle, 2" before the T3 flange.


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## 16v lover (Feb 17, 2007)

my autometer egt manual said you can run it in the center right behind the turbo or in the DP 6" away from the turbo.


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## BoostedDubVR6T420 (Dec 4, 2009)

I actaully prefer it to be after the turbo as you recieve the best temp reading, and can see the temperatures that are running through the turbo. Just my .02.


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## Stroked1.8t (Jan 9, 2004)

it is Exhaust Gas Temp, so you want to know the temp of the exhaust coming out of the head, not a combine temp. if you measure in the collector or after the turbo your numbers will not be the same as right out of the head. it doesnt matter what the temps are after the turbo, the turbo can handle far more heat then your aluminum head and pistons. numerous places online say to mount the sensor a couple inches away from the head. my egt probe is in the #1 exhaust runner 2" from the head, been that way for 2 years.......just my $0.02


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## KubotaPowered (Jan 27, 2005)

EGTs can be up to 250 degrees lower post turbo. I like having it either in the turbo flange or manifold just before the turbo.


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## 'dubber (Jun 15, 2004)

I also placed mine in the #1 cylinder runner a couple of inches away from the head, supposedly the #1 runner is the hottest one. :beer:


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## benzivr6 (Feb 16, 2001)

Thanks for the great info guys


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## GTijoejoe (Oct 6, 2001)

KubotaPowered said:


> EGTs can be up to 250 degrees lower post turbo. I like having it either in the turbo flange or manifold just before the turbo.


 I agree.... as gases flow over a turbine they expand, this pressure differential will also change the temperature differential over it. The most accurate EGT reading is before the turbine, than you normally try to pick which cylinder runs the hottest (this comes from experience) or you can put it at the collector area where all the runners merge.... 

Post turbo will also still give you an 'idea' of what your EGT's are, also easier to mount.... honestly that is where mine has been for years.... more importantly is actually your airfuel


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## vr-vagman (May 15, 2010)

If you use individual EGT reading(which is actually meaningful) your sensor shoud be placed at distance equal to about your exhaust runner diameter from the head. It should be placed on the outside of the header turn(if there is turn at that distance). There's almost no sense to place EGT probe in comon part of the collector since it will read average EGT from all your cyls and you'll never know if one is actually running very hot and ready to melt something. ....And yes - before the turbo! There could be seen about 120-140C difference across the turbo in modern diesels. 

Just my 2c


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## kevhayward (Mar 13, 2007)

Individual EGTs is fine if you have the ability to monitor 6 temperatures at once, and have the ability to tune any weak or rich cylinders individually, for which you will need a standalone. 

Mounting the probe pre-turbo comes with a risk of losing the turbine wheel if it snaps off, but is the best place to read the temps in my opinion. 

I have measured pre and post turbo and haven't seen anything like a 150+ deg C difference like people claim. 50 deg C, tops. 

I'm happiest with this method, but each to our own. To get an idea of individual cylinder tune, I check the plugs, and then trim the fuel accordingly.


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## 1.8t67 (Dec 7, 2008)

kevhayward said:


> Individual EGTs is fine if you have the ability to monitor 6 temperatures at once, and have the ability to tune any weak or rich cylinders individually, for which you will need a standalone.
> 
> Mounting the probe pre-turbo comes with a risk of losing the turbine wheel if it snaps off, but is the best place to read the temps in my opinion.
> 
> ...


 did you leave the probe protrude THAT far into the manifold???? 

i have mine stuck into the runner about 2" from the head on #2 (1.8t). the tip of the thermocouple sticks out maybe 1mm into the runner.


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## VDUBIN (Jun 28, 2001)

the probe is supposed to protrude about 1/2 to 3/4 of an inch into the manifold at least.


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## vr-vagman (May 15, 2010)

1.8t67 said:


> did you leave the probe protrude THAT far into the manifold????
> 
> i have mine stuck into the runner about 2" from the head on #2 (1.8t). the tip of the thermocouple sticks out maybe 1mm into the runner.


 I'm sorry to steer a bit off this thread but don't you think that that exh. mani's design is bad? It is very popular in vr community though


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## [email protected] (Jul 1, 2009)

dead center in the collector.


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## kevhayward (Mar 13, 2007)

Yes the ATP manifold is [email protected] in my opinion. Poor quality chinese cast that's like 50 bucks wholesale and sloppy runner design. BUT.....what else is there that will fit? Kinetics is nice, but has fitting difficulties on RHD UK cars. SPA Turbo, does the job, but has quality concerns. AFI Tubular, very nice too, but big $s. 

I wasn't sure how far to push the probe in. I wanted it right in the gas flow really. Too far out in the perimeter didn't seem right to me, but with no reference EGT data from VW for VRTs, how do we know what's right and what's wrong?


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## benzivr6 (Feb 16, 2001)

I wasn't sure how far to push the probe in. I wanted it right in the gas flow really. Too far out in the perimeter didn't seem right to me, but with no reference EGT data from VW for VRTs, how do we know what's right and what's wrong?[/QUOTE] 

That's why I made this thread up for hopeful future reference


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## GTijoejoe (Oct 6, 2001)

benzivr6 said:


> I wasn't sure how far to push the probe in. QUOTE]
> 
> Normally you try to put the probe tip in the middle of the flow as much as possible :thumbup:


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## 1.8t67 (Dec 7, 2008)

kevhayward said:


> Yes the ATP manifold is [email protected] in my opinion. Poor quality chinese cast that's like 50 bucks wholesale and sloppy runner design. BUT.....what else is there that will fit? Kinetics is nice, but has fitting difficulties on RHD UK cars. SPA Turbo, does the job, but has quality concerns. AFI Tubular, very nice too, but big $s.
> 
> I wasn't sure how far to push the probe in. I wanted it right in the gas flow really. Too far out in the perimeter didn't seem right to me, but with no reference EGT data from VW for VRTs, how do we know what's right and what's wrong?


 you can put the egt thermocouple anywhere you want....but it should not stick that far into the manifold. regardless of what engine/make you own. 1/16 of an inch is to much. pull that thermocouple out a bit. 



VDUBIN said:


> the probe is supposed to protrude about 1/2 to 3/4 of an inch into the manifold at least.


 no.


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## rtolay (Dec 14, 2005)

i just turn my vr6 on tonight, i have a afi tubular turbo manifold and cylinder 1,3,5 r the hottest by almost 250 degrees


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## rtolay (Dec 14, 2005)

i just realize why i always melt cylinder 5 which is the hottest out of the 6


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## kevhayward (Mar 13, 2007)

1.8t67 said:


> you can put the egt thermocouple anywhere you want....but it should not stick that far into the manifold. regardless of what engine/make you own. 1/16 of an inch is to much. pull that thermocouple out a bit.


Why? It's been that far in for 50K miles and 3.5 years daily use without a problem.
The Dynotune manual didn't specify a mounting depth.


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## clarksongli (Nov 4, 2003)

the closer it is to the gas stream the more accurate the reading....

but there really is no "right" answer.....the closer to the motor, the hotter the gas and shorter life.

farther away, cooler gas, longer life.....the probe will rear whatever is seen at the tip of the TC, you just need to take that into account when reading the EGT gauge.

if it is post turbo, understand the temps are much higher in the inlet to the turbo. Same with the placement further outside the gas stream.


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## kevhayward (Mar 13, 2007)

Thanks for explaining!

I guess mine is in a little far. I will drop it down into the middle of the manifold, which will hopefully place the tip in the middle of the exhaust stream.

Whilst googling the subject yesterday, one website said EGT probes should not be in the exhaust permanently. They are for taking sample readings only.

What's your opinion on that? I've had the same probe in for years, but after reading that, I'm concerned it's going to break off and take the turbo out now!!

The readings never really change much, so I suppose there's no real need to have it on permanently.


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