Pyrometer Mounting???

[CWade]

Might as well get my 2 cents worth in. I have been a heavy duty truck tech since 1974. On two or three occations I have seen a pyro sending unit fail. It is a very rare occurance unsually caused by metal coming out of a damaged engine.
A turbo under load spins at a very high rpm, perhaps 100,000 rpm. It only takes something the size of a pin head going through it to destroy it in a matter of seconds. I will agree that a pre turbo installation will respond quicker, but I am not going to take a chance of a drill shaving going through my new turbo ! My probe is drilled and tapped through the exhaust brake housing - behind the turbo.
All factory installs on the big rigs are post turbo.

Charlie Wade

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2001. 5 3500 Quad Cab 4X2
HO, 6 spd, 3. 55AS, Jacob's brake, patriot blue, 22K Reese 5th wheel,Reese digital brake controller, Isspro pyro & boost gauges, Snap-On tool box

 

[RAPID RICK]

Dave,
Cat,Detroit & Cummins put the t-couple
after the turbo & a 3406E cat or a sreies 60
Detroit or a N14 Cummins cost a LOT more than
$6000. Rick

 

[Neal Cassady]

Rick,

Read the whole post, they are not "bombed" from the factory. With factory fueling and timing they shouldn't be able to exceed critical temps.

Dave D

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2001. 5 QC, LB, 4x4, Auto, 3. 54, Everything but Leather, Bright Silver Metallic, ARE K Series, Diprocal EGT, Boost and transmission Temp in an Autometer Dash Pod, Westin CPS Platinum Step Bars - Black on Stainless

[This message has been edited by Dave D (edited 03-02-2001). ]

 

[Royal]

DAVE D, your 100% on target. The big rigs are
mostly run at factory spec's. Withthe new fuel
systems it would take a system malfunction to over temp one. I have mine pre turbo so I get accurate EGT's. I can't add or subtract or guess what my EGT is. The cooling temp. at
post turbo is also a myth. You need to know turbo bearing housing tempature and oil temp in the bearing area to prevent oil coaking and varnishing on the bearings. I believe a temp. P/U near the maim housing is as accurate as in the tin exaust pipe 6 inches
from the turbo. Just my 2 bits. Give me hell.

 

[illflem]

Royal,I won't give you hell. I don't give a Dookie where the big rigs mount their pyros,I know where mine is mounted for a no guessing game reading. As far as drill chips damaging a turbo,as long as you do the best you can to remove them any that might be missed will be blown out by the exhaust on the first startup,most likely before the turbo starts to spin certainly long before it reaches 100,000 rpm. If you're still concerned remove the turbo before drilling,it will only add a half hour to the job. 2¢

 

[RAPID RICK]

Illflem,
You stated Banks has installed 10,000 kits pre turbo,Cat,Detroit & Cummins
have installed HUNDREDS OF THOUSANDS post-
turbo. I won't be changing to pre-turbo any
time soon. My opinion (for what it's worth)
Rick

 

[Neal Cassady]

When vehicles leave the factory they are not "bombed". The timing and fueling are set not to exceed the design parameters of the engine. In that case a pyro mounted after the turbo would be fine and provide the info needed for cool down after a run and a general indication of the work load on the engine. When you exceed the design parameters of the engine a man has got to know his limitations (thanks Clint). The post turbo gauge protects a $600. 00 turbo, the pre turbo gauge protects a $6000. 00 engine.

Dave D

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2001. 5 QC, LB, 4x4, Auto, 3. 54, Everything but Leather, Bright Silver Metallic, ARE K Series, Diprocal EGT, Boost and transmission Temp in an Autometer Dash Pod, Westin CPS Platinum Step Bars - Black on Stainless

 

[Morphious]

I just got through putting my pyro in pre-turbo. I did this while installing my 4" exhaust system. 4 bolts to remove the turbo from the exhaust manifold as well as the down pipe unhooked. Stuffed a rag inside the turbo housing and then drilled and tapped the manifold. After that was done, I used a shopvac to clean everything up. I have now given it hell for two days without a problem.

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99 2500 4x4 QC Std transmission, Purple, 10 Disc Sony Changer, 285x75Rx16 BFG Mudders, Gooseneck hitch, 275lb King Klaw front bumper, Towing/Camper setup.

DDIII's, Exhaust, TTPM, Clutch, Guages are now on order.

1965 Chevy 1/2 ton Pickup, 350-350hp/2spd powerglide, PS, PB, Disc Brakes on the front, Tilt, Fuel Cell, 3. 73 posi.

26ft Gooseneck Flatbed Trailer.

1960 Farmal 340 Diesel Tractor

 

[RobbyRam]

Seems to be about even: Pre vs Post turbo.
How about a 'fist fight' #ad


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Y2K Awesome Black LB 3500 QC SLT, 24Valve ETC ISB, 4x4, 4:10 LSD, DTT Custom prepared Auto transmission VB, Power Edge 'EZ', DD2's, K&N, Polished Stull Billet Grill/Fog inserts, Chrome Smitty-Built Step Rails, Mopar Chrome-Tipped Mud Flaps, A-Pillar mounted West-Tach Turbo/Pyro/Trans Temp gauges, Rancho 9000's, Diamond Plated Tool Box, + a bunch of other stuff. Fact:The First Fords' had 'DODGE' Engines! The new PSD's need them!

 

[Fireman Dave]

Just did the pyro today. Post for me. I put it in for shut down temps. My engine is 100% stock.

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2001 2500; SLT; 4x4; QC; LWB; Auto; 3. 54 LS; 265s; Camper; Tow; Sliding Rear Window; Travel Convenience Group; Cab Clearance Lamps; BedRug; Forest Green

 

[EMDDIESEL]

This has become an interesting topic. I have mine mounted Pre-Turbo, it is my personal opinion, (and the vast majority of others) That the reading PRE turbo is MOST important (An ideal setup is to have a thermocouple Pre and Post turbo). The problem with getting a reading after the turbo is the exhaust side turbo housing acts like a heat sink and absorbs alot of the heat from the engine exhaust and radiates it to the engine compartment (Thats why they make insulation blakets, which by the way, are HORRIBLE for turbos, but that is another story). So an EGT reading after the turbo will always be much cooler then Pre-Turbo and therefore will not help you (As much) in determining when it is safe to shutdown and when the EGT is reaching a dangerous level.

People who install them after the turbo say "Well i just add like 2 or 3 hundred degrees to the Post Turbo temp and i can figure out what the pre turbo temp would be" WHY NOT JUST INSTALL IT RIGHT THE FIRST TIME!and not have to add numbers (Which is inaccurate anyhow). This whole thing with people saying they are installing them after the turbo out of fear of the Thermocouple breaking and destroying the turbo is pretty far fetched. I have NEVER heard of a catastrophic thermocouple failure, EVER. I am not saying in cant happen, i am just saying the odds of it are so slim, its not worth getting improper EGT readings. You stand a better chance of frying your turbo from incorrect EGT readings then the Thermocouple hurting anything. I have been in the Railroad/Construction Diesel industry for over 10 years and my father (now retired) was a diesel mechanic for 48 years. I just spoke to him and he said he has never heard of that happening. and he has worked on Cummins, Cat, Detroit, Fairbanks-Morse, etc. I have worked on 20 Cylinder EMD diesels that cost almost $600,000 and they have EGT probes mounted before there $80,000 turbos. Again, anything is possible, but as was mentioned by someone else, you stand a better chance of being struck by lightning, Or having a pebble rip through your aircleaner and destroying your turbo then your Thermocouple doing it. The only way it could break is if an object in the exhaust hit it, and if that was the case, the broken Thermocouple is the LEAST of your problems. Short of it being hit by something, the only other threat is if it were to melt (My guess would be in the 3000 degree range to do that, need i say more). Just because Cummins puts them after the turbo on some of thier over the road trucks, does not mean its the best thing to do for Rams. Most over the road trucks are not driven like a pickup truck and dont have fancy fuel computers, boost controllers and all the other gadgets we use that raise EGT's to dangerous levels where monitoring them is critical. I am stating my personal opinion, and the opinion of MANY highly regarded Cummins Ram experts such as Jannetty Racing, TST, etc. Why not do a poll and people can list how they have theres, Pre Turbo, or Post Turbo?. Any thoughts?

 

[Paul]

My pyro tip has been mounted pre turbo for almost 50k miles. I pull it out once a year and check it for errosion. Still looks like the day it was installed.

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Paul A. Schmidt
95, 4X4, SLT 2500, 5 spd. , 4. 10, 270 hp. ,675ft. lb. TST, AFC spring kit,215hp. injectors,16cm2 turbo housing, Pacbrake, Walker muffler,
GearVendor O. D. , CenterForce Dual Friction clutch.
Eastern PA.

 

[MCummings]

Like this... #ad


#ad


MerrickNJr

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1998. 5 Dodge 3500, 2wd
5-Speed, Light Driftwood
Replaced the Resonator and Muffler with 6ft of 3" Aluminized pipe.
3. 55 rear-end
A. R. E. Camper
Michelin 245/75/16's

[This message has been edited by BOMBER_101 (edited 04-09-2001). ]

 

[Archive]

This is my 2nd Cummins with my pyro installed before the turbo. Drill and tap Dont tap too deep. 2 to 3 threads screwing in the probe fitting by hand. These are pipe threads. Too deep and it wont tighten up. Hope thi helps #ad
.

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2001 RAM H. O. 6Sp 2500 SLT 4x4 Quad Cab, 4Wheel Disc, 4. 10 Limited Slip, Fog Lights, Muffler removed, Silence Ring Gone, Autometer Pro Comp Boost & Pyro, Banks High Ram (Red), Cmmins Red valve cover, K&N RE-0880, Skyjacker 2. 5 lift Class 2, 7218 Dual steering stabilizers, Custom Pro Fab Trackbar (sweet), EGR Flares (nice fit), Centerline Comet III 16x9. 5 with 305/70R16, Smittybuilt stainless nurf bars, THIS IS NOT A HOBBY, THIS IS AN ADDICTION !!! MAINLINING DIESEL !!!

 

[Nemies]

Here are pictures of a post-turbo installation (done this weekend). Close-up and far away...
http://www.digitalmafia.org/~nemesis/pix/2001-04-07/post-turbo.jpg

http://www.digitalmafia.org/~nemesis/pix/2001-04-07/post-turbo-close.jpg

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Kees C.
99, 4x4, 2500, 5spd, HD, LSD, SB, QC, Sport, Forest-Green, Cab-Lights
Rhinoliner, toolbox, dual Firestiks


[This message has been edited by Nemies (edited 05-08-2001). ]