Exhaust Stud Removal

Talk and Tech about turbocharged 924/944/968 cars
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danmartinic
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Good morning gentlemen

I now have a thread chaser set.. new exhaust gaskets
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These are my punches and pilot bit.. not sure if any of these are what is referred to above?
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Tom, the stud in question would be #3
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I thought maybe I could just use the manifold as a guide somehow but this one is a slot not a hole
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Do you need precise measurements of, say, exhaust gasket holes?

#21

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Tom
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danmartinic wrote: Sun May 03, 2026 7:02 am Good morning gentlemen

I now have a thread chaser set.. new exhaust gaskets

IMG_3220.jpeg

These are my punches and pilot bit.. not sure if any of these are what is referred to above?

IMG_3216.jpeg

Tom, the stud in question would be #3

IMG_3217.jpeg

I thought maybe I could just use the manifold as a guide somehow but this one is a slot not a hole

IMG_3218.jpeg

Do you need precise measurements of, say, exhaust gasket holes?
Got it, will post a drill jig soon. I'll get the measurements and such off my spares. :) Given the challenge of your situation, I'm thinking the jig should accommodate steel drill bushing of at least a couple of sizes, so you can start by trying a smaller reverse bit to see if the remaining stud will break free and turn out. But you may need to install a helicoil -- some broken studs make preserving the original aluminum thread virtually impossible.

#22

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danmartinic
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I'm not good at reading these things.. the threaded bit guides are 1/2"? The pitch is definitely 1.5
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Not sure if the jig they fit into is of any use
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#23

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jeyjey
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Your calliper is reading 17/32" (13.5mm), which doesn't make much sense.

Are the bit guides metric or SAE?

#24

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danmartinic
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I pulled out the digital caliper with a fresh battery... makes more sense now
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Looks like M14

On imperial setting...
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Above are both 'shaft' and thread measurements

As for pitch... both 1.5 and SAE 18 fit nicely
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I feel M14 x 1.5 will suffice

Just came from two hardware stores where M14 only comes in 2.00 pitch

#25

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jeyjey
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9/16"-18 is UNF. M14 does have a fine-pitch spec (at 1.5mm), but it's not very common.

My bet would be on 9/16" UNF.

#26

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Tom
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Try screwing one into a 944 lug nut. They happen to be M14 x 1.5 :shifty:

#27

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danmartinic
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Bingo
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