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Good morning gentlemen

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

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.

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

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

Are the bit guides metric or SAE?

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

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

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

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

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.

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

Bingo

Here you go!

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