Archived EGT Probe

[FCisler]

I've drilled and tapped my exhaust manifold for the EGT probe. My problem is I didnt' want to snap off the 1/4 NPT tap in the manifold. I only have about two turns of the probe fitting into the manifold. Is that enough? Is the pressure inside the manifold high enough to blow the fitting out? I heavily greased the tap so as not to allow metal filings to enter the manifold and made only half a turn of the tap, removed it, cleaned it, regreased it and continued on several times. I've contacted the Tap manufacturer and asked if their are torque specifications for this tool and they said their is none I should go by "feel". I have a heavy hand, and have been known to snap bolts. I have put about 300 miles on the truck with no problems so far. Am I worrying too much? Help?

 

[bmoeller]

I think mine is in about 2-3 turns. No problems. The manifold doesn't have a very thick wall anyways. Might only be holding by 2-3 turns.



It should be fairly easy to tap. It if starts to feel a bit hard (as if it snagged on something), after going somewhat easy, back it out a bit (if not all the way) to break the chip, then go in again.

 

[dpuckett]

As long as you keep everything straight, and dont put any sideways or off-center loads on the tap, you should be fine. But, if it works with 2-3 threads, I woudltn worry about it. Seems like my 1st Gen manifolds only go about 4-5 threads deep, anyway. Personally, I'd go a little farther, but I've also done half a dozen, so I have some experience. To each his own.



Daniel