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tapping ex. manifold for EGT

1376 Views 18 Replies 8 Participants Last post by  barracuda_440
Any suggestions? I got my gauges wired up and everything, now its time to tap that manifold for the Egt and finally turn up the pump and slide that plate forward!
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Take your time, Try not to tap to fast (AKA back it out every half turn or so) Dont use Grease but use some PB blaster on your tap, That will also make things easier.

When drilling your manifold, use a fine point punch to get a pilot started. Then use your 23/64 (if your using a 1/8NPT Therm. Coup.), Drill slow, Dont try to force to hard on it!
Try to use a high quality bit , I use alot of Dewalt bits that have a nice point on the end for starting! As you get closer to punching through take it very slow to avoid binding your bit. Make sure your hole is straight by keeping the drill as straight as possible! Also use some PB on the bit as you drill!

Once drilled you've got a few options, Start it with the hole open to blow shavings out... Now before anyone disagrees lets keep in mind that 90% of the drill shavings exited via the bit. Your tap dust is so fine that it really wont cause any problems!

If your worried, Just take a shop vac and put over the hole!

Remember that this is NOT a hard process, Just relax and take your time, Once you get the feeling of the tap , you'll be much better!

If you need help anyone here can help!
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thanks fish fry i really appreciate you walking me through it. Im going to go get my bits and tap tonight and maybe have at it tommarow night or so. With the stock trans and 125k miles would it be ok to turn up my pump and slide my plate forward for alittle extra power?
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Gauge Install

2nd on taking your time. that's the key.
The gauges i got are the Dipricol, with the danin wiring harness, i got the 1/8th NPT tap, but im am not 100% sure what bit to use. I dont plan on taking the turbo or manifold off.
I use a Letter R drill. :thumbsup

Where can i get a Letter R drill bit? they dont have them at murrays, or ace hardware....
i would suggest taking off the manifold to drill it then blow it out with an airhose so you dont get chuncks of metal in your turbo
Letter R bits can be hard to find, But I assure you a 23/64 Will work just fine! Really only (IRC) about .5 MM diffrence.

I would refrain from turning any fuel to your truck unless your planning on a new transmission. You'll get much more life out of your stocker if you leave it be!
Where can i get a Letter R drill bit? they dont have them at murrays, or ace hardware....
I found mine at a pawn shop...
Letter drills are very common in the machining industry.

Letter R drill, .339

23/64 drill, .3594

i put axle grease or vasoline on my taps and bits when i drill them. then use a shop vac to get the remaining shavings out. then start the truck and last install the tap.
Thanks guys i really apreciate the help....

One last thing

sell my plow for me? haha
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BBRams right, letter bits are very common in the world of machining. my grandfather gave me several full sets of his from when he was a tool and die maker.
If you need one barracuda, just let me know.

BBram, where is chelsea compared to Clarkston? I am about 5 minutes north of great lakes crossing mall if that helps any. The guys from coaltrain where supposed to come up this weeeknd and do timing and bring me a 5in turbo back, but i havent heard from them yet. Give me a call at 248-342-2865 if thats easier.
Well guys im about to go tap that thing, i guess the worst case scenario is i mess it up and have to buy a 3 piece manifold like i was origionally planning on haha
WELL?? how did it go? hope well :thumbsup
Well i didnt end up doing it, decided to go look at a plum crazy cuda i found with my dad....hopefully the guy want to sell it, and doesnt know what hes got :]

The reason i didnt tap it is becuase i couldnt find where the wire from the EGT probe goes into the wiring harness for my Danin harness. My buddy is coming up tommarow to help me out.
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