I was wondering how far from the end of the turbo i should put my probe off for my pyrometer. I dont want to do a pre-turbo setup becuase i am afraid of the tip breaking off and going in the turbo, just not a chance i want to take. Right now in the stock exhaust (which is only 5 feet long and then dumps down) i have the probe about 3-4 inches back if i remember right, and i have ben figuring it is 300 degrees cooler back there. Thanks

 

To me thats not a good idea, especially if you plan on bombing your truck, Iv searched high and low on a few different forums and have not heard of any breaking off. You can doit, its your truck, just add 300* to what ever temp you are showing. I would get it as close to the turbo as possible.

Max egt on a stock truck is:
1250* pre turbo
950* post turbo

 

I seriously doubt it would break off, maybe in my case melt off, 1600 deg. probably isn't too good for anything, heck maybe its higher, thats as high as my gauge goes!

But seriously, I understand your concern, I just hate having to guess what real temps are. I would put it as close to the cast elbow as I could get it. But as always, its just my opinion! Good Luck!

 

Post turbo is a poor choice.
The 300° rule doesn't always hold true, there can be up to 500° difference between pre and post turbo.

I've been working on these trucks and visiting message boards related to them for over ten years and have never heard of even one thermocouple breaking off.

 

You can either pay for a turbo(if you are unlucky enough to have it break), or you can pay to have your motor redone when you melt it down because you have no idea what your temperatures are.... Its your choice. I wouldnt pay for A pyro if I was going to put it in a place where I wouldnt get accurate readings.

Eric

 

Instrument Installation: The pyrometer instrument should be mounted securely to minimize vibration; flexible brackets are not advised. Locate in best viewing position. If lamp is removed during installation, lamp hole should be plugged or taped over to prevent dirt or metal particles from contaminating the movement.

Thermocouple Installation: Various threaded mounting adapters are available, i.e.1/8 NPT, 1/4 NPT, 3/8 NPT, and 1/2 NPT. If not specified, 1/4 NPT will be supplied.

Location will vary depending on application and engine. On turbo charged engines, whenever possible, thermocouple should be installed in manifold before the turbocharger - this will give the highest temperature indication and the best response time. Hewitt thermocouples are designed to tolerate this location safely and carry a lifetime warranty. If mounting pre-turbo is not possible, a lower temperature of 150-200F will result when mounting after the turbo.

For non-turbo engines, thermocouple may be installed in the manifold before or just after the exhaust pipe flange, as is convenient.

Connecting terminals have staggered lengths to insure correct polarity, plus color match to extension wire. A plastic heat shrinkable tube is supplied with the thermocouple and should be slid over the terminals after connection is made with the extension wire and shrunk in place with heat for insulation purpose.

Extension Wire: Standard available lengths are 7 ft. minimum, 12 ft., and 14 ft. maximum. If longer length is required, 2-conductor 18 gauge wire may be added between extension wire and instrument, also available color coded from Hewitt. When installing the extension wire, care should be taken to stay clear of exhaust system and chafing areas. Secure with tie wraps, etc. to eliminate wire movement. Terminal connections to pyrometer are designed to insure correct polarity.

 

OK, if i were to put in front of the turbo, do you guys suggest putting it in right before the turbo, or little farther up.

 

Here you go, follow these directions.

http://www.piersdiesel.com/TechPyroInstall.htm

 

I too, was leary of a probe breaking off, but the unit that came on the Isspro was substantial and put my fears to rest. My only thought would be if there is a life expectancy (years)?