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Engine Specific Info and Questions => IDI Engine => Topic started by: hamradio on May 21, 2008, 06:39:46 pm

Title: Where to tap an NA manifold for egt?
Post by: hamradio on May 21, 2008, 06:39:46 pm

So,
The turbo for my na is put on hold for a few weeks.  In the meantime, I'm going run it NA.  Where should I tap the manifold for an egt probe?  It seems like the manifold goes 4-2, and then into one at the toilet bowl.  I thought it was supposed to be in the exhaust flow from all 4 cyls.  Would it be better to tap the downpipe, right at the toilet bowl, for it?

Title: Where to tap an NA manifold for egt?
Post by: zukgod1 on May 21, 2008, 08:10:22 pm

That would work, just get it as close as ya can to where all 4 merge so you get a good reading.

Post up your readings when your done will ya?
I'm curious what a NA runs at

Title: Where to tap an NA manifold for egt?
Post by: James8485 on May 21, 2008, 10:52:32 pm

i would think that the best spot is in between the 4 bolts of the turbo on the manifold, thats where i drilled and taped mine....so your reading the temp coming outta the 4 chambers right before it goes into the turbo
its thicker there as well so you can get lots of thread and dont have to worry about striping it. no need to center drill and such as cast is soft and as soon as you apply some presure from the drill is starts doesnt wonder even on alittle bit of an angle. just make sure you drill on an angle so the prob doesnt hit anything when you insert it in to the manifold.
its really quite simple (alot easier with the manifold off though)

Title: Where to tap an NA manifold for egt?
Post by: hamradio on May 22, 2008, 05:05:13 am

This is on an NA manifold. :)

Title: Where to tap an NA manifold for egt?
Post by: rabbitman on May 22, 2008, 03:23:08 pm

I remember someone on the forum saying to put the probe as close to the head as possible otherwise the gasses have cooled some. Also seems like the guy said cylinder number 2 is the prefered one 'cause for some reason it got hotter, airflow was worse maybe.

PS. Measuring all four cylinders won't make the gauge read higher, this is one case where 1000 degrees X 4=1000 rather than 4000oF :D.
Hopefully someone smarter will chime in. :?

Title: Where to tap an NA manifold for egt?
Post by: hamradio on May 22, 2008, 04:59:10 pm

I know.  I figured all 4 cyls were better, as maybe one cyl would run cooler or hotter than the rest, as maybe the injector has an issue or something.