Thermocouple Comparisons

[DocB]

This write-up is at the end of a long learning curve as I searched for the best thermocouple for my application. All will work just fine on our trucks, but there are some small differences. I, like most of you, just assumed what the vendor sent was what was suppose to be the "one". Well, we do have some choices. For those of you planning on installing an EGT gauge, you might want to read this first. Be informed, and ask for the particular thermocouple that best fits your needs. This may be too much info for some, and doesn't really make a difference, I've been told, but for those of us that are anal about our truck, installing the mod best suited for us the first time around feels good.
We've all read the long threads about drilling, tapping and the dreaded steel shavings. This issue is also addressed.
Here are some pics of some of the various types of ISSPRO Thermocouples available for our PSDs. These are of the drill and tap variety. All are adjustable in length. (How far the tip sticks into the pipe).
Please pay close attention to the length of the probe and the diameter of the threaded plug. Also, notice the connection of the thermocouple wires to the lead wire.

[DocB]

The 3 thermocouples side by side. All are length adjustable. #1 is 4" long, and has nut and bolt connections to lead wire, which get shrink wrap over the connection for protection. When adjusted for length much of the back end will stick out into the engine compartment. #2 and 3 are 2 5/8" long, just enough to center the probe tip in up pipe and have WeatherPack connectors to the lead wire.
http://i196.photobucket.com/albums/a...couples005.jpg

The one on the left is 1600* and 1/4" NPT brass
The one on the right is 2000* and 1/8" NPTF steel
http://i196.photobucket.com/albums/a...couples006.jpg

A closer look:
http://i196.photobucket.com/albums/a...couples007.jpg

[DocB]

# 3 was the best choice for me because:

1. 1/8" NPTF drill and tap hole, smaller hole, less steel shavings, less work. (Also, if you screw up you can go to the larger).
2. 2000* probe, better? Probably not for our application (we'd better not see more than 1600*!) but I believe in overkill.
3. WeatherPack connector, like the name says, weather tight. Same as OEM connectors under our hoods. Easier install.

So there you have it. Be informed, Be well.

Bruno.....

BTW, don't ask how I got to take the picture of all 3 together.

[CSIPSD]

Isspro is the only one to offer the weatherpak connector...