Don't want to start a this spot is better than this spot thread for where to put the thermocoupler. From everything I have read the most accurate reading would be pre-turbo. There are too many variables that can cause different readings for post turbo setups. One could be the intercooler, if it gets somewhat blocked, will cause different readings. I know on fords, and prob all the rest of the diesels that its not the turbo that is as important as the pistons. In the powerstrokes the pistons are aluminum.. see the attached thread I copied from Diesel Stop Website
"The International engineers explained it a lot different during a national rally of members of TheDieselStop touring the PSD engine plant in Indianapolis.
Don't worry about high egt hurting the turbo. It's made put of steel and can take a lot more heat than the aluminum pistons. If your engine blows up because of high egt, it will be the pistons, not the turbo, tearing things up.
The pistons begin to deform at about 1,250 egt. Eventually, the top ring will jump out of the deformed piston, and then you have bits and pieces of the remains of the steel ring punching holes in the top of the deforming (melting) piston, and or pieces of ring getting in the valves and plugging them up. Whatever the exact results, when the piston deforms, your engine is toast.
That's why the International engineers insist that if you hot-rod your PSD, then install a pyrometer with the thermocouple (sender) mounted pre-turbo - in the up pipe or the exhaust manifold. Then use 1,250º as your red line. They said you can run all day at 1,200º pre-turbo egt, but stay away from 1,250.
A tiny bit of research can confirm this. Look up the melting point of aluminum."
I think I will keep mine Pre-Turbo. And Pete, I try to keep mine under the 1250 mark. I think the Duramax is somewhere close to that. I think I read somewehere that about 1300 is the max.
Pete check out this site. It has a lot of good info on it..http://www.dieselplace.com :angry: