Boss 351 distributor identification

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Does anyone have clear pictures of the identifying features on a Boss 351 distributor or a link to a reliable example. I have a distributor I am going to sell but want to verify its identity first. It's from my dad's parts left over from a car we restored years ago. We didn't use it because he thought it was faked. bought it from a Hemmings ad back in the day.
 
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Years ago, fake/counterfeit parts such as carburetors, distributors, etc., for '71-73s was not a big problem. Everyone was so busy hating on the '71-73 and Mustang II's that no one gave a second thought to wasting any time counterfeiting parts for these outcasts. The big money was those types of parts for any K code engine, Boss 302, 429, 428 CJ/SCJ. But now that most of those vehicles are in the collector's hands, they finally figured out that the '71 429 and Boss 351s are now bringing big money and worth a second look. We've all seen the NOS $8,500.00 Boss carburetor and $1,200.00/ distributors. As far as the fake part shysters are concerned, the bull eye target has now moved to our butt cheeks!
I commend you for wanting to verify the authenticity of the distributor you have. If your distributor is a production-installed (OE) unit, the housing should be branded Autolite and have a cast "12127" with a stamped "D1ZF-DA". There would also be a date stamp below the 12127 indicating the actual date of manufacture. Typically, there would be on average, a 3-month time frame before the vehicle's production date. Lots of variances on the assembly line, so that is not set in stone.
Since Ford was transitioning to Motorcraft in '72, any service replacement distributors sold after the Autolite stock was depleted would be branded Motorcraft. Most of those I have seen would have the "D1ZF-DA" stamping but no production date. Eventually, Ford stopped stamping the housing and started using a metal tag much like the ones used on carburetors that everyone liked to throw away. One of the vacuum advance screws fastened this tag to the distributor. The production installed vacuum advance was the "Banded style," although it's debatable how many of those are still in use. The service replacement vacuum advance and those on later service distributors were the "Crimped" style.
The distributor housing for all 351C engines was sourced from the '68 460 Mark III Lincoln, so all will have a Lincoln C8VF-12131-B casting number on the housing. The bare housing never had a service part number assigned to it and was never available separately. So that number cannot be used to definitively ID a Boss distributor.

This is probably a little more than you asked for, but hopefully, there is some helpful info you can use to ID your distributor! :)
 

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The part number looks legit to me. Was the date code area shined up by you or did it come to you shiny? I think it decodes as 1970, August, 26, very early. Chuck
 
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Question; I think I read on here, that the Boss dual point distributor has a "bearing of sorts" that the two plates rotate on and not like a standard distributor where the plate sort of just slide over a plastic plate, for want of a better description.
Is that correct?
 
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Hey lalease,
Like Chuck, my first reaction when I saw the shiny spot on the date code area of your distributor was concerning. But, spit shines are effective for fast spot clean-up! Date-coded parts are just as important as the period-correct parts are to Concourse level restorers. Something the fake part pirates have known for years. They have made untold sums of money on "Manufacturing" fake Boss, Shelby, 428, 429 CJ/SCJ, and many other Ford and competitive make parts.

I hated reading where forum member 71TexasBoss was taken advantage of by trusting what he thought was reputable sellers. I'm sure some sellers are victims themselves when buying collections from sellers they trusted and reselling items they thought were authentic. I'm also positive many do know what they are doing. The temptation to sell a dipstick that Ford retailed for $4.20 and mark it up to $450.00 or more is too great.
There are eight different "D1ZF" 351C distributors. The majority I have seen have the D1ZF lined up neatly due to them being stamped with the prefix once the housings are pulled for Cleveland use. Once the application and calibration are set for the build, the suffix is stamped. That is why some of them don't seem to match the neatness of the prefix and are not always straight, and have the look of being stamped as an afterthought. There is still a lot of opportunity for some low lives to "Cook" some letters and numbers.

@Geoff The breaker plate in the Boss distributor is a single-piece unit with a roller bearing that allows the upper plate to rotate. The standard two-piece single-point plate has nylon bushing/bearings on the lower plate that the upper plate rotates on. This two-piece breaker plate dates back to 1959 and was replaced in the late '80s by a single-piece design but still used nylon bushings. :)
 

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@Geoff The breaker plate in the Boss distributor is a single-piece unit with a roller bearing that allows the upper plate to rotate. The standard two-piece single-point plate has nylon bushing/bearings on the lower plate that the upper plate rotates on. This two-piece breaker plate dates back to 1959 and was replaced in the late '80s by a single-piece design but still used nylon bushings. :)
Thank you secluff, just what I thought I'd read. I'll pass that info on to my buddy who has bought what he "thinks" is a Boss distributor. Hope he's right and not yet another victim of fraud.
EDIT: oh wouldn't it have been nice if ALL these Autolite distributors had this bearing set-up instead of the cheap nylon pads we are stuck with.
Also wouldn't have been nice if Pertronix had used this arrangement for their "Ignitor III" module. IF they'd done that, the PIII would be a good buy.
 
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I guess I won't be selling this distributor, upon further cleaning I'm now positive it was ground down and stamped ZF DA. the shiny spot where the date code is, is legit. But the dark shading where the ZF and the DA are stamped is where the low life ground down the original letters. Dad bought this in the 80s as the UPS date was still on the box. along with the name and address of the guy from Dearborn Hts. I'm surprised at scamming Boss parts that long ago. Time to keep digging through Dad's treasure.
 
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If it is indeed a fake, it is pretty well done. I would have no issues selling it as a fake for someone who wants to have the a "correct number" distributor on his Boss 351. As long as you are upfront on the fact that it was re-stamped and it is a fake, in my opinion it is fine to sell it. If it is a dual point distributor, it is still worth a good amount of money. Look at eBay, a nice 351 single point distributor is not cheap anymore. Someone will want that distributor as a cheap alternative to get their Boss 351 with a correct number distributor. No one, will ever notice that re-stamp when the distributor is on the engine, even a judge... I would put it up on eBay and have people just bid on it, highest bidder gets it. The only issue here is that you sell it to someone who 6 months later tries to sell it as real, but that is really on them, not you.
 
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