pyrometer install - poll
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From: Texas
pyrometer install - poll
This is a poll for those of you who have installed a pyrometer:
1. Did you install before or after the turbo?
2. If before the turbo, did you remove the turbo for drilling into the manifold or not?
3. Which is the most accurate way to monitor temps?
1. Did you install before or after the turbo?
2. If before the turbo, did you remove the turbo for drilling into the manifold or not?
3. Which is the most accurate way to monitor temps?
that is if you want to see what is really happening. 
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From: Minneapolis, MN
Re:pyrometer install - poll
Pre turbo. Also, take the time to do it right. Remove the turbo or at least move it over far enough to cover the inlet with some cardboard and have room to get your hand in the manifold. Stuff a rag in the exhaust manifold past where you are going to drill. After drilling, clean out the shavings in the manifold and remember to remove the rag! Take your time.
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From: Spruce Grove Alberta
Re:pyrometer install - poll
If you were in competition (drags or pulls etc.) I would go pre turbo. I just pull a fiver so I installed mine in the Jake brake between the Turbo and the butterfly of the ex brake. This is where Caterpillar, Cummins and Penske (series 60) all install them in class 8 on and off hiway trucks so if it is good enough for them it is good enough for me.
If I was installing it pre turbo I would definetly remove the turbo.
Jim O
If I was installing it pre turbo I would definetly remove the turbo.
Jim O
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From: Alberta Canada
Re:pyrometer install - poll
Mine is after the turbo and came with instructions for installing only downstream.........having said that...obviously there will be temp differences pre and post...but it's all relative...the operating range is higher pre turbo and so if i was running consistently 700-900 and saw a sudden rise to 1100..then i would know something was up..and a pre turbo guy was running consistently 1000-1200 and saw 1500....his foot would get light... as long as you have a gauge and a good idea of where your truck should be running temp wise i think you have it covered...unless youre running a drag truck
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From: San Angelo Texas
Re:pyrometer install - poll
I have run pre and post on the same engine at the same time and have seen as much as 400deg difference. On a hard pull it was making 875-925 post turbo and was over 1300 pre turbo. Talked a customer into moving his probe on an 03 with injectors and box, he was able to get 1000deg post turbo. After moving the probe he was seeing 1400 deg in the manifold, and it was getting there much faster than what the post turbo probe showed.
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From: Plainfield, IN
Re:pyrometer install - poll
Pre turbo I pulled my turbo down, and used a piece of sheet aluminum to cover the turbo inlet. I greased up my drill bit and tap, after looking at the sheet when finished I am glad it was in there. For those with out a 3rd gen remember the turbo hangs below the manifold.
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From: South East Michigan
Re:pyrometer install - poll
I went preturbo. It's not that hard to do either. I dropped the turbo before drilling and tapping. With the turbo being vertically below I don't think it's possible to drill and tap without dropping lots of debris into the turbo. You have four bolts to undo at the manifold. Two are easy to access from the engine compartment and the rear two were easier to access from under the truck using a long extension and universal joint under the socket. I also unbolted the exhaust at the first hanger attached to the trans housing. Once this is done push the turbo down as far as possible which for me was about a 1/2 inch. I put a piece of thin cardboard into the opening and then did the drill and tap. Carefully clean of the cardboard when done and then slide it out from the opening.
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From: Lake Nona, Florida
Re:pyrometer install - poll
I'm planning on going post-turbo.
I don't plan to modify so I don't think I've got issues.
Cummins recommends post (for unmodified), so I figured I'm OK.
My thinking is that I'll get more accurate cool down temps.
For the "post turbo" folk. I guess you can't tap the pipe wall there? Did you weld on a bushing or just use a clamp? The clamp seems Mickey-mouse to me and I can get the welding done for free...
I don't plan to modify so I don't think I've got issues.
Cummins recommends post (for unmodified), so I figured I'm OK.
My thinking is that I'll get more accurate cool down temps.
For the "post turbo" folk. I guess you can't tap the pipe wall there? Did you weld on a bushing or just use a clamp? The clamp seems Mickey-mouse to me and I can get the welding done for free...
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Re:pyrometer install - poll
I went post turbo. My engine is stock, no boxes or other bombs and I don't pull heavy loads up steep mountains. My only concern is cool down temp of the turbo. Post turbo is for that.
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From: Laredo, Tx, 7 hours south of Dallas
Re:pyrometer install - poll
http://www.fast-diesel.com/docs/egt.html
http://gatewaydieselownersassociatio...amp;how_to=EGT
Some Quotes, taken from other sources...
I just compiled this from a couple places I was reading. Hope this can help somebody.
Merrick
http://gatewaydieselownersassociatio...amp;how_to=EGT
Some Quotes, taken from other sources...
I did not remove anything to drill the manifold. I used a Dewalt cordless drill and a succession of bits starting with the smallest bit I felt would not twist off pushed pretty far in the chuck. I also used the grease on the bit trick
I sold a Ram CTD to a guy who rebuilds Cumins and Detroit diesels. He is one of a few mechanics in this county who will even touch a diesel. Since he has been working on them for 20-odd years, he invariably knows more about them than any 22 year old ever could. He mentioned the part abouth the tip breaking off (I had the t-couple mounted pre turbo) and trashing the turbo, and most likely the engine with it. I have since read here and on other truck related sites that that is an urban legend, and if the tip breaks, you have BIG problems. Anyway, that, along with his comment about any AFC adjustments having no efect on the fuelling/ performance of a VE pump, killed any confidence I might have had in his ability as a B series machanic. Aparently, this urban myth is still floating around, due to longevity of careers of mechanics and others "who know their stuff.", as opposed to research and development, and real world experiences. I noticed in my early 91, that I NEVER EVER hit 900 deg the week I had the pyro mounted post turbo; had a machine shop drill and tap the manifold, and I could EASILY hit 1350 up a 5% grade empty. At 20 psi at the high temp, there goes the 10 deg per psi boost.
I just compiled this from a couple places I was reading. Hope this can help somebody.
Merrick