I'm ordering a three gauge pod from Autometer. Trans, Boost, and Pyro. The instructions they have on their website say to install the EGT probe in the drivers side manifold...

I'm also looking at getting a 4" turbo back Stainless Steel exhaust system soon.

Before looking at Autometer's instructions, I was originally thinking of putting a bung in the new downpipe up near the top and putting the probe there. That's where I remember it being on all the big trucks I used to drive...

Aside from the obvious answers I would expect with this question; Where should I put the probe???

 

Drilling and tapping this may get you worried, but its easy to do.



Here goes the trans temp sender.

 

I'm not too worried about the work, just where is the best spot for accurate readings.
If it goes in the drivers side manifold, I'm only getting a reading from the drivers side...
Or is that even an issue?

 

If you had two gauges, put one in the left, and one in the right. For anything but a heavily modified truck, you dont really need to worry about it.

 

The exhaust manifold is the most accurate location. If you put it in the downpipe it will read low by 200° to 300°.

Gauge ****** put in two pyro meters, one for each exhaust manifold.

 

Yeah, after I typed that I thought; It's all stock right now. Probably not that big a deal.

Thanks for the pictures.

 

The side is not an issue, as temps between each manifold will be consistent enough for everyday use. What is an issue is pre vs post-turbo temps. The reason for the pyro is to monitor exhaust temps coming out of the combustion chamber. The pistons in the Powerstroke are made of aluminum, and aluminum melts at just under 1250 degrees. Prolonged driving at exhaust temps well over 1250 can and will cause catastrophic engine failure. Going over 1250 degres in short bursts is fine, since there is not enough time for heat soak. But say you are pulling a large trailer several miles up a mountain grade, then yes, EGT's are extremely important to monitor, and holding temps over 1250 all the way up the mountain will usually result in cracks in the pistons.

The temps in the exhaust manifold are about as accurate as you will get. If you install the probe in the downpipe (post-turbo), you will not get an accurate reading of exhaust temps. The reason is that there is no linear correlation between pre and post turbo temp readings. If the post turbo pyro reads 900 degrees, the actual pre-turbo temps could be anywhere from 950-1400 degrees. The reason is that the turbo absorbs some of the exhaust heat, and the amount of heat transfered depends on the amount of fueling, the boost levels, exhaust backpressure, ambient air temp, altitude, engine load, RPM's, etc. So there are a ton of variables to account for, which is what makes post-turbo EGT's useless.

The reason truckers ran post-turbo pyros for so many years is that the old probes were prone to break off and thrash the turbo. If the probe was installed in the downpipe, it wouldn't hurt anything if it broke. Today's probes no longer have that issue, and will last a very very long time.

 

Excellent info. Thank you.

 

Nice write-up, Curtis. Put it on the driver's side up-pipe or manifold. Pre-turbo.

 

I put mine in the up-pipe. A little easier drill/tap job. Just don't run the tap all the way through. Keep running it in & out adding lube, and once you get about half way down with the tap, try test fitting the adapter. If it's not enough, put the tap in and go a little further. The tap I used was about three threads out for a perfect fit: