Pyro location

[BigYellowIron]

What is the pros and cons of the location of the pyro being post turbo? Should I think about moving it pre turbo? What is the limit on exaust temp?
Thanks,
Adam Harman

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"POWERSTROKE THIS"
Adam Harman
95 auto red and white #6 tst , eagle alluminum wheels. Still BOMBING

 

[Missouri Mule]

BigYellowIron,
As I recall post turbo will give you better reading for cool down time and turbine tempature (since turbine wheel is cooled by engine oil). Could be wrong though.

Pre turbo would give you accurate tempature of cylinders. This would help when pulling large trailer up very long steep hill. If your temps get to high you would need to put less pressure on go pedal.

Looking through TDR's there is 300 degree difference when running hard between pre(1300) and post(1000), these are danger zones (melt down can occur at these temps).
The difference at cool temps(shut down) is about 50 degrees.
Issue 20, Technical Topics has some info about Egt in general. Also same issue in Shade Tree.
Will look for more articles in TDR see if i can find any other info.


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Bill Thomas
Missouri Mule - 96 Wht 4X4 ST CC,5 spd, 3. 54, 8 ft bed, 1 ft high cheater boards.
99 Freightliner bl/wht FL60 ISB-5. 9 24v,215 hp,520 tq,6 spd, 3. 59 nsr,16 ft box, 19. 5 tires,Wt/gvw 11,000/23000

 

[The patriot]

Pre turbo is generally better than post turbo, for an accurate reading.
The (very slight) possibility DOES exist for the probe to become broken, thus entering the turbo. This would wipe it out instantly.
I put mine post turbo, because I believe it's easier to install.
Eric

 

[illflem]

Adam,pre-turbo is the best all around. The post turbo location,while being easier to install due to not having to worry about metal shavings from drilling and tapping damaging the turbo,will only give a rough idea of combustion temps unless you use a complicated formula. I guess it is possible for a probe tip to break off and do damage,but I've never heard of it happening. Go for pre-turbo.

1300°preturbo is about the temp when you need to think about backing off. 1500°would be ok for a short period. Think 1300°pre translates to around 900°post.

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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)

 

[dpuckett]

I put mine perturbo- use a little grease on the drill bit, and all should be fine. A few small shavings wont hurt anything- just let it idle a little before driving it. I used a shop vac to suck out all the shavings. No problems after 10K miles. I figure a little extra effort is worth saving an engine. At 7000 ft, my EGTs will get to 1000 deg empty. Wont see it if I had it post turbo. I have heard it is somewhere in the 200-500 degree range for a difference. Not much good IMO.

Daniel

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Daniel's current truck: 1993 W350 club cab, 5 speed, treadplate aluminum flatbed, 4. 10 rear end, straight pipes, K&N, "slightly" tweaked pump. ISSPRO color coded pyrometer and 50psi boost guage. NRA Life Member (since age 12) and d@mned proud of it. IRBCTS.

 

[Koa Man]

I posted this question on the 24V forum, but asking it here also. Has anybody out there ever had a EGT probe break, mounted either pre or post turbo?? If so, what was the result? Many guys say they mount theirs post turbo in case it breaks, but like illflem said, I never heard of it happening yet.

 

[illflem]

Adam,how about just adding a pre-turbo sender with a switch to toggle the numbers to one gauge,best of both worlds. You have to be careful that the switch material is the same as the wires-copper. If you use a switch with plated connections the junction between the copper wire and nickel(??)plating can generate a small amount of current that will throw your readings off. Will just cost you the price of the sender and switch,use the same type sender as you already have. In fact you may have to replace the sender if you move it anyways. When they are installed the probe gets crimped and shouldn't be moved or adjusted without risk of damage/poor seal.

Also read this- https://www.turbodieselregister.com/ubb//Forum4/HTML/004628.html



[This message has been edited by illflem (edited 02-27-2001). ]

 

[BigYellowIron]

Thanks Illflem The information was great
thanks
adam

 

[John_P]

Adam, Koa Man(Wes), illflem:

My pyrometer probe is "pre-turbo" for the
reasons both of you listed. I recently
had it changed out as it was almost four
(4) years old. The tip of the old one
was "crystallized" from the heat. It
looked to me like it was just about
ready to "come apart" but my son said
"he didn't think so. " I don't know... .
but I will say this; I intend to inspect
it more regularly now and believe I will
change it about every 24-36 months.

Although... ... if I let it "come apart"
then I will have a reason to get the
HX-40!!

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John_P

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Red '96 4x4 2500 Auto 3. 54, TST #5, Major Pump Mods(By "Scheid Diesel") 370 Diamond B Injectors, Gov. Spring kit, AFC Spring kit, Banks Exhaust, Prime Loc, Cummins Chrome Kit,Psychotty Air Filter, Pro-Torque Converter, BD Valve Body, BD Pressure Loc, Isspro Gauges, Sendel 16" Alum Wheels w/ 33" BFGs

 

[Koa Man]

John P,
If a probe failure will only result in the loss of the turbo and no other damage to the engine, then I won't even worry about it. If a turbo blew apart, would the oil cause engine runaway?? Like you say, a broke turbo will just give me a reason to get another turbo like the HX40 or maybe even twins. #ad

 

[illflem]

KoaMan,I've never heard of it happening on the TDR and also asked Banks about it,they said they've had some thermocouples fail,but none have fallen apart. According to Banks' website they have over 10,000 of their kits installed on Dodges alone,that's a lot of experience to draw on,and doesn't count the number of PSDs and motor homes that also have their kits. The rep did say that they have had quite a few gauges fail though,mine did after 5 years,started reading 100°high. Banks replaced it no question,love that warranty.

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95' 25004X4,AT,Driftwood,Banks Stinger,Warn fender flairs and running boards(work truck)
95 3500,5 speed 3:54,BD E-brake,Driftwood,Banks&Psycotty,34,000 GCVW apple and tractor hauler(works harder truck)

 

[BigYellowIron]

anyone,
Would you recomend that I move it to the pre turbo before I do injectors?
thanks for your replies
Adam Harman