Can you save me from hours digging through my parts boxes? I need the thread size for the upper seat belt bolt (#6) that goes into the side of the pillar.

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TIA

There was/ is? some standard that requires all cars imported to the US to have 7/16-20 bolts holding them in. I can't remember if it is the upper or lower that is a special bolt that has a collar for the plastic spacer, though?

Close, but not quite. Tried a 7/16-20 but it doesn't get past a single thread. Must be 11mm. Good thing Ace is only 5 min away.

Thanks.

I would question whether the bolt you tried was actually 7/16-20. If it isn't, I'd wonder if someone cross-threaded something else in there.

I put my door braces in with 7/16-20, and I've also made hold-down eyelets with 7/16-20 for my bus, as all the seatbelt holes on the floor and wall in there are SAE also.

There was a prior thread on this topic. It's metric...

Try Repa 11 mm x 1.25 pitch. I know these work at all seat belt anchors on early 914s.

Bob

must be different on 72's, edit, and my 71 is the same? Must be only 70's are different?

Figured it out, 7/16in = 11.1125mm and 20 tpi is equal to a thread every 1.27mm, so the difference falls within the tolerance of manufacture of the bolt. The head is metric for sure though.

Thanks guys. I always like the details. Since Ace doesn't carry any 11mm, it looks like I'll be diggin through the boxes.

I was involved in a debate on this several years ago on this board.

I was certain that it was metric and someone else was certain that it was 7/16-20.

I tried both taps and the one I sourced from McMaster Carr M11x1.25 worked perfectly.

I assume that there may be something to the 7/16-20 thing being reality. Most aftermarket (racing belts) come with this hardware and all the Eye Rings I see are all 7/16-20. I believe that the 7/16-20 and the M11x1.25 are close enough that either fastener may screw into the threads.
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All bolts used in the fastening of seat belt hardware and anchors for cars destined to be sold in the US are the same diameter and thread pitch. It's the law. Makes sense that the manufacturers would use them in cars destined for other markets, as well. Simplifies things and keeps costs down.

The Cap'n

Ended up actually getting the 7/16-20 to work. I couldn't find my metric fasteners. The threads did need to be cleaned with some WD-40 and we're good to go.

Amazing how much information can surround a simple fastener.

Just the info I was looking for.
Heading down to the farm supply store to take a look at the Hiem joints to redo my door braces.