PDE Up-up pipe install Q&A

You've got less heat, not more, without the cat...cats generate heat (oxidation process).

I thought you were worried about heat?!? Some like wrap, some don't. One truth is all manufacturers void warranty coverage on cracks, etc if components were wrapped. That should tell you something ;-)

With a catless uppipe you no longer need the EGT probe. It is only there to monitor the temperature of the catalyst in the factory uppipe, which you have now removed. While it is possible to put the probe back in if there is a bung for it, it won't serve any purpose and it is fairly common for them to fail a short time after being reinstalled in a catless pipe. The cause of the failures may not be temperature but the increased exhaust flow, since in the OEM pipe the probe is located within the catalyst matrix and now it will be exposed to the full exhaust flow. You're best off sealing the bung with a bolt and doing the "resistor mod" by installing a 2.2K ohm resistor in the connector where the probe now connects.

Probably best off using factory gaskets, and be sure to torque the bolts properly. Don't be surprised if it leaks anyway, they often do.

Most people with modified turbo cars like to run an EGT...and not to monitor the temperature of the catalyst. The temp is a great diagnostic tool to keep an eye on pre-ignition, help decide boost level, etc. TG

True, but the question here is what to do with the factory EGT probe when installing a catless uppipe. You're correct that once the car has been modified for more boost and power it's a good idea to monitor the EGTs with a gauge, however this requires an aftermarket probe along with the gauge, and the probe should be mounted in the exhaust manifold rather than the uppipe. The factory location is not ideal for this purpose, and the existing probe isn't compatible with aftermarket gauges.

So should i plug it or insert the probe into the new bung?

I say plug it, remove the probe completely and do the "resistor mod". Should you decide to put the probe back anyway, don't be surprised to see a CEL in the near future, probably with a P0546 code indicating a blown probe.

I just realized that the bolts that come on the up-pipe are not there...

Obviously the prev. owner did not give them up when he sold me the item. Can the bolts be taken from the factory up-pipe (I was thinking of using two nuts backed tightly into each other and then using them to unbolt the studs from the OEM piece). Otherwise, since the PDE unit is threaded couldn't I just go buy five new 10x1.25 Stainless Steel bolts for use?

Mike