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pyro sensor location

  • post

    Votes: 11 17.7%
  • pre

    Votes: 51 82.3%
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Discussion Starter #1
which do you prefer for the pyrometer sensor, post or pre-turbo?

:popcorn:
 

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You have to be pre-turbo to get the most accurate temps.

Randy
 

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pre, hands down. But my egt's like to climb, thankfully my motor is prepped, But boy could I use some more air, 65psi ain't cuttin it.
 

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hell, 100psi probably wont for all this fuel I got, lol.
 

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Discussion Starter #5
post for me, right in the turbo down pipe.

i'm a little paranoid abort the sensor melting....
 

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I drive by my pyro. In overdrive, 5 MPH can have a 100 degree EGT fluctuation easy. I like to cruise at 1200 degrees, what would I be cruising at if it was post turbo? I would have to put a thermocouple in pre-turbo to figure it what the max post-turbo reading was...

I'd rather kill a turbo due to a pyro probe than kill a turbo due to a piston slushy through my valves.

I do run a 1/4" thermocouple in the name of longevity, though.
 

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post for me, right in the turbo down pipe.

i'm a little paranoid abort the sensor melting....
The thermocoupler is designed for the heat, I've seen the survive 1900*F and not melt, juat out of curiousity, where did you get an idea like that?
 

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unless you run 1800* for minutes on end, you have nothing to worry about.
 

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Im going to put mine in the post turbo. I dont want to take the manifold off or drill the manifold with it on. Im only running the Smarty jr and everyone ive talked said EGTs are not a problem with the jr. Post turbo should be fine for my application.
 

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Discussion Starter #10
The thermocoupler is designed for the heat, I've seen the survive 1900*F and not melt, juat out of curiousity, where did you get an idea like that?
it happens.... faulty sensors...

form a mechanic who works for a mining company.
 

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Agreed, But in my application accuracy is eccential, and I'd rather lose a few grand in turbos than another $15,000 engine.
 

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yes, there is about a 300 degree difference between my Edge (mounted post turbo) and my autometer(mounted pre turbo) the difference is pretty consistant except for low speed/idle.
 

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Pre turbo here too..I am not worried about the thermocouple failing at all.I am sure the engine would melt down before that
 

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The problem is that you don't have a constant 300 degree drop. The drop is dependent, heavily dependent, on what kind of turbo you're using, what kind of housing you have, your current boost level, where you are on the map and how much (if any) you're afterburning.

On a truck that's going to be tuned for its entire life, there might be a 200 degree drop one day, then a 400 degree drop after you install injectors... Who knows?

Thermocouples do fail, or at least some used to do. A lot of the post-turbo guys are steeped in big rig tradition, where they are placed post-turbo for that reason on most trucks. But, on stock big rigs off the assembly line, you can know what the post-turbo reading really means. On a modified truck being tuned it's hardly useful at all when you're playing on the knife's edge.
 

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Discussion Starter #16
yes, there is about a 300 degree difference between my Edge (mounted post turbo) and my autometer(mounted pre turbo) the difference is pretty consistant except for low speed/idle.
that's very helpful info

just add 300 degrees. at idle post all ways takes longer to cool down due to the turbo spooling down.

:peelout
 

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do you actually have to pull the manifold off to be able to drill into it on the 6.7s?
 

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there is a perfect spot on the manifold to drill for the 6.7. Lots of room but you may need to remove one little hose I believe it is one of the hoses for the EGR. If you take your time there is virtually no chance of hurting anything when you drill the manifold. Drillbits by there design remove particles out from the hole. I grease up the bit go slow and keep the shavings out of the hole while I go and I have never had ANY problem.
I don't see the point of putting it Post. You are looking for acurate reading and it has been proven time and time again that post turbo EGT's are not acurate for bombers. If you are just looking for a guage to play with and watch while you cruise around in a stock truck then put it in the downpipe.

Chris
 
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