Topic: 12 point Disc Brake Caliper Bolts, Question

[k-code]

I'm restoring my KH disc brakes and the 12 point bolts that attach the two caliper halves together have been replaced by regular grade 8's at some point.
I can't find a source for the correct bolts for my Dec '64 build. I've looked in the usual places and it appears AMK B-12700 is listed as the current replacement but I think that's the '67 change? It's somewhat confusing identifying if thats the bolt for caliper to bracket or caliper half to caliper half.
Anyone know of a source? If not, what is acceptable?
Thanks, Andy

[J_Speegle]

Anyone know of a source? If not, what is acceptable?

Donor cars would be an option. Might consider checking with the T Bird owners and suppliers also. Believe their hardware may be like Mustangs that year and all of them came with disc brakes so would increase the possibility of finding what you need

[J_Speegle]

Here are the head markings and design your looking for

[k-code]

Thanks Jeff. Yup, appears to be unobtaniam now.

I assume the parts suppliers have gone with the '67 style which is hex head like the bolt directly above in the pic?
Since my post, I did find this

https://www.aftfasteners.com/7-16-14-x-1-3-4-12-point-flange-bolt-plain-oil/

but of course head markings won't be accurate, and 1/8' longer which is manageable with a thin washer, or slight modification....but then again, not accurate.

I've perused a couple T-Bird parts venders and nothing so far.

Is it acceptable from a concours point of view, to go with the '67 hex head style?

[CharlesTurner]

There are usually core calipers on ebay or online for sale.  An expanded search to calipers will likely be the only way to source the correct bolts.

[J_Speegle]

Thanks Jeff. Yup, appears to be unobtaniam now.

I assume the parts suppliers have gone with the '67 style which is hex head like the bolt directly above in the pic?
Since my post, I did find this

https://www.aftfasteners.com/7-16-14-x-1-3-4-12-point-flange-bolt-plain-oil/

but of course head markings won't be accurate, and 1/8' longer which is manageable with a thin washer, or slight modification....but then again, not accurate.

I've perused a couple T-Bird parts venders and nothing so far.

Is it acceptable from a concours point of view, to go with the '67 hex head style?

Given the forum and the focus on restoring of the car back to as they were built I think you can answer your own question. If in a show - would some judge look the other way?  Of course but only way to know for sure if something will be "acceptable" would IMHO be to have the correct part and even then sometimes you may have discussions but you should be able to prove and support your choice at that point

[Bob Gaines]

There are usually core calipers on ebay or online for sale.  An expanded search to calipers will likely be the only way to source the correct bolts.

+1 .  Of course you might get lucky and find individuals but if you don't like wasting time narrow down from various cores for sale. 

[k-code]

Thanks for the suggestions. Caliper cores on Ebay are still $3-400 and most have had their 12 points replaced at some point. Don't often come across parts that aren't reproduced on the early Mustangs but this appears to be one.

[Bob Gaines]

Thanks for the suggestions. Caliper cores on Ebay are still $3-400 and most have had their 12 points replaced at some point. Don't often come across parts that aren't reproduced on the early Mustangs but this appears to be one.

I believe there are less expensive alternatives. PM sent.

[J_Speegle]

If there are still companies that are rebuilding originals there is likely a decent size pile (sure they just toss them out) of the original hardware since it appears common practice is replacing them with new bolts. Unfortunately no easy way to gain access to the tossed ones 

[k-code]

I've got a call into two potential sources, but won't know for a day or two.
There are a couple fastener companies that make ferry cap screws but of course won't have the correct markings on the bolt head.
I had assumed it was a 7/16"-14 but after measuring in the garage this morning realised its something else, 1/2"-13 ??. At least thats what I have in there now.
The pic you sent Jeff shows a washer, and the MPC shows a washer also. Is it lock or non lock?

[jwc66k]

I had assumed it was a 7/16"-14 but after measuring in the garage this morning realised its something else, 1/2"-13?.

The bolts documented in the "1964-65 Mustang Chassis Assembly Manual" (AM0005 pg8, 378225-S2) are 7/16-14X1 5/8 in L with a 49/64 inch shoulder length, shoulder diameter in not specified. Service includes (75 ed, Ill Sect 20.1 p8) 382101-S which is a 7/16-14X1 3/4 in L, nylon lock and a drilled head, no shoulder shown, no washer of any kind is used. The bolt is not 12/13 although that thread is used for the adapter to the spindle.
The 12 point bolt is not documented in any Ford or AMK documents I can find - so, no part number.
Both my 65 GT Fastback (SJ 11May65) and 66 GT Fastback (SJ 18Oct65) have 12 point bolts. They are real, they exist. If you do find some, don't forget to get a socket or some type of 12 point dive to install.
Jim
The service text (75 ed Sec 21 pg 2) is in disagreement as to the threads used.

[k-code]

My MPC specifies either 379027-S or 378773-S with 34809-S as the washer...it doesn't say what type of bolt it is so I am assuming 12 point as thats what was originally used.

The bolt used for caliper to adapter is 7/16-14 X 1 5/8 but when I thread those into the 12 point location they are too long without a washer and the thread seems loose, if that makes sense. So I dug out my thread gauge and sure enough the caliper to mounting plate bolt is a 14 and the grade 8 bolts that someone previously used to bolt the caliper halves together are a 13. It's all very confusing. I doubt very much a previous owner re-tapped the holes to a 13 but you never know.

I called NPD again today and confirmed no repro is available, and the fellow I spoke to said he's never had anyone call for one before.

I'll run down to my local fastener shop tomorrow to confirm the thread, length etc for a starting point.

If someone has a spare 12 point, unmounted, to measure, that would be helpful.

[J_Speegle]

My MPC specifies either 379027-S or 378773-S with 34809-S as the washer...it doesn't say what type of bolt it is so I am assuming 12 point as thats what was originally used.

That is what dozens or more shows

[Bossbill]

Caliper adapter is 7/16-14.

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