Does the older style "original" pacBrakes (98-2000's)have a manufactured port for a pyro probe?

I'm not sure... :think:At any rate I wouldn't use it. I would still drill and tap the manifold for a more accurate temperature reading of the exhaust gas temperatures.

Elknih,

It would be better to have the pyrometer BEFORE the turbo. It is not from an accuracy standpoint but from a relative standpoint. (see lower definition)

You (and me and mike and everyone else) is concerned about the temperature of the exhaust entering/affecting the turbo. Therefore it is much wiser to actually measure the exhaust at this area. Theoretically you could infer actual temperatures from a downstream pyrometer, but is it worth it? Your data will also be comparable to other peoples data.

(steps on soap box)

The term Accuracy has to do with the pyrometer's ability to tell you what temperature it is seeing. The closer the pyrometer is to telling you the real temperature (of the exhaust in this case), the more accurate it is. This is totally a function of the pyrometer (and the gauge manufacturers ability to read the millivolt signal and display it), NOT its location in the exhaust stream. You could put the pyrometer in the exhaust tip. It's accuracy is not effected (assuming that the cool temperature is not out of the target accuracy window of the gauge system). It will tell us with utmost accuracy totally irrelevant information!!

It comes down to, the closer that you are to measuring the data that you really want, the better off you are. No guessing, no fudge factors etc.

(steps off soap box, ready to catch cabbages:hyper:)

Hag

I am equipped with a pre and post pyro and there is a huge difference in readings. Pre is manifold and post is turbo elbow at exhaust.Poking along the highway in cruise mode, pretty much the same readings give or take a few degrees. Put a load on it, climb a hill or pull a trailer, huge differences upwards of over 700 degrees.Both gages are marked with the standard green, yellow and red zones. A good portion of the time when I am under load while towing up a hill, I can balance the pre pyro around 1100 degrees and the post pyro will read over 1600.Around town while towing in traffic, the post pyro is all over the scale as I up and downshift in traffic.Obviously I drive by the pre turbo pyro and you should also be monitoring that temp not at the turbo itself.Jeff