Taping Manifold For EGT

[Baselyne]

Where on the turbo exhaust manifold should I drill to put the threaded bung for my EGT probe? I know i gotta weld it in place but where should it be?

I saw a picture on here before but I couldnt find it, search wouldnt help me

[jtanguay]

just drill & tap it. welding cast would suck.  put it where all exhaust streams meet so that the thermocouple gives a good reading

[blkboostedtruck]

just drill & tap it. welding cast would suck.  put it where all exhaust streams meet so that the thermocouple gives a good reading

drill and tap is the easiest!!!!

 you can weld cast! but is a special process! preheat to atleast 300 degrees evenly and stick weld with 1/8 nickel rod for machineability or 7018 HR4 1/8rod for non machineability! meaning that  the 7018rod you will not be abel to drill,tap,mill, becomes very hard after welding and mixing with the hgh carbon thats in the cast!
welding cast is not bad! just need to know the process! I like welding it know that i learned the process !
Duane

[jackbombay]

Drill and tap is easiest, drill a pilot hole first and then the correct sized drill bit fo the tap you are using, you can find that with google. Practice on a scrap piece of steel, its not the same as cast iron, but screwing up you exhaust mani would suck.

[saurkraut]

Cobalt drill bits are your friend:

[Dirtrag2]

saurkraut, are all K-type sensors the same diameter?  if so what size drill bit and which tap should I use?

reason is i'm upgrading my turbo on mt 1.9 to a garett T3 and if possible I would like to drill and tap before I bolt it to the
engine, I haven't got the egt yet

[jackbombay]

saurkraut, are all K-type sensors the same diameter?  

 my VDO uses a 1/8" NPT and my isspro uses 1/4" NPT.

  The VDO reacts a fair bit quicker than the isspro, and was cheaper. Plus its a fair bit easier to not screw up when drilling and tapping a smaller hole than a bigger one.

[saurkraut]

Thats an 'Aircraft Spruce' thermocouple in the picture.  Its 1/8 NPT too, same as the VDO thermocouple.

[TOW'D]

Is there any advantage to using a EGT on a N/A diesel?
Does that thermocouple have to be mounted on the manifold could it be mounted  in the exhaust pipe?
cheers
hank

[Baselyne]

I was told (and it's states above in this.....

just drill & tap it. welding cast would suck.  put it where all exhaust streams meet so that the thermocouple gives a good reading

Im thinking the closer it is to the tubro ....pre turbo is best!!!? is the better reading??? correct me if im wrong

I was thinking of test tapping the one in the N/a manfold to grab a solid reading then once i turbo the n/a I could get another EGT reading!

It would be cool to note the difference and then see just what I can do about that putting the oil cooler and intercooler...
could be fun

[jackbombay]

Sure, practice on the NA, if it doesn't seal perfectly its no big deal as there is no backpressure like a turbo, and the numbers would be good for comparisson.

[jackbombay]

And pre turbo is the only reading that matters, you want to know how hot the exhaust is going into your turbo, not coming out which is notably cooler at high boost pressures, and how much is a guess.