Carb advertised as 1968 GT500 NOS Holley on Craigslist

[JWH]

I saw this on the local Craigslist, not mine but posting for comment and someone may be interested. Asking $3,000:

https://mail.google.com/mail/u/0/#inbox/WhctKKZGZCmktXpgFZTrHVSBLCvnpwsHXvGgCXptfqvcrDnKKwRhXmGGNhgPbtrxFzfWLnl

NOS new old stock 1968 Shelby GT500 carburetor
Never mounted
Never had fuel
Stamp ID:C8ZX 9510 A
List:4129
Date:7A4
F metering block:5719
R metering block:5661
Tag ID:C8ZX
Date:7LD

Bill 3 zero 3 3 eight 6 6 two two 8

[Coralsnake]

Found it!  Got them saved

[Coralsnake]

https://denver.craigslist.org/pts/d/strasburg-nos-1968-shelby-gt500-carb/7649813795.html

[98SVT - was 06GT]

Funny date code -  Holley says date should be 3 digits - no letters?
https://www.holley.com/blog/post/holley_carb_hunter_s_guide/

https://www.mustangtek.com/4150/C8ZX-9510-A.html

[Coralsnake]

Not at all

Too bad Holley cant remember their historical legacy

Year\month\week

A is November

B is December

[98SVT - was 06GT]

Not at all

Too bad Holley cant remember their historical legacy

Year\month\week

A is November

B is December

I was thinking letter was month but I was leaning toward a natural conclusion that A was January. The other one I linked to is 3 numbers - 832 2nd week of March 1968. I'm assuming (yep I know the definition) that they went to all numbers in 1968......

[JWH]

Date: 7 A 4
7 = 1967
A= November
4 = 4th week of November

*a tip of the cap to Dan Case for posting an excellent guide to the date codes on Holleys, both original and Service replacements on this site years ago.

[Royce Peterson]

Not at all

Too bad Holley cant remember their historical legacy

Year\month\week

A is November

B is December

I was thinking letter was month but I was leaning toward a natural conclusion that A was January. The other one I linked to is 3 numbers - 832 2nd week of March 1968. I'm assuming (yep I know the definition) that they went to all numbers in 1968......

No the November / December continued to be represented by A and B respectively as long as Shelby Automotive was in business.

[98SVT - was 06GT]

No the November / December continued to be represented by A and B respectively as long as Shelby Automotive was in business.

Is this right then to mark the 2 digit months?
1 = Jan
2 = Feb
3 = Mar
etc to
9 = Sep
0 = Oct
A = Nov
B= Dec

[JWH]

Here is a reposting of Dan Case's excellent explanation of how to decode the date codes on Holley carbs: 

Holley® Carburetor Date Codes


Part I  O.E.M. Carburetor Date Codes

O.E.M. models, O.E.M. assembly line models, utilize a three digit date code; numbers or numbers and letters are stamped just below the Holley "List" number on the front face of the choke housing air horn. (Service assemblies set aside during production for making cars will have dates in the production time frame.)

Example:      List - 3259
                    4 B 5

The first digit signifies the year the carburetor was manufactured, 1964 in this example.

The second digit represents the calendar month of production, in our example December. The table below details the complete set of twelve month codes.


   Month Codes (Center Digit Of Date Code) for O.E.M. Carburetors

                           Month            Code

                           Jan. ------------- 1   
                           Feb. ------------- 2
                           Mar. ------------- 3
                           Apr. -------------  4
                           May  ------------- 5
                           Jun  -------------  6
                           Jul  -------------   7
                           Aug  ------------- 8
                           Sep  ------------- 9
                           Oct  -------------  0
                           Nov  ------------- A
                           Dec  ------------- B


The third digit designates the week of the month produced, the example above was made during week five.

Therefore the List - 3259 above, for a 1965 MUSTANG GT350 289 c.i.d. engines, was manufactured during the fifth week of December 1964.





   II Service Replacement Carburetor Date Codes

Service replacement carburetors, those available over the counter years later at O.E.M. dealers, speed shops, auto parts stores, etc, utilize a four digit date code; numbers only appear in this case, stamped in the same location as before under the "List" number. The service unit codes are expresses as "Julian" dates with the model year of manufacture indicated by the additional and last of the string fourth digit. The Julian date codes table for service models is given below.         

   Month Codes (First Three Digits) for Service Replacement
   Carburetors

             Month          Julian Date          Leap Years *

              Jan. ---------- 001 - 031 ---------- 001 - 031
               Feb. ---------- 032 - 059 ---------- 032 - 060
              Mar. ---------- 060 - 090 ---------- 061 - 091
              Apr. ---------- 091 - 120 ---------- 092 - 121
              May  ---------- 121 - 151 ---------- 122 - 152
              June ---------- 152 - 181 ---------- 153 - 182
              July ---------- 182 - 212 ---------- 183 - 213
              Aug. ---------- 213 - 243 ---------- 214 - 244
              Sept.---------- 244 - 273 ---------- 245 - 274
              Oct. ---------- 274 - 304 ---------- 275 - 305
              Nov. ---------- 305 - 334 ---------- 306 - 335
              Dec. ---------- 335 - 365 ---------- 336 - 366

         * Leap Years: 1964, 1968, 1972, 1976, 1980, etc.

As an example of a service replacement carburetor lets examine a current Ford Motorsports Boss 429 replacement unit.

   List - 4647
             2916   

This carburetor is definitely a service model since it has a four digit date code. The fourth digit signifies 1986 (It was purchased from Ford in early 1988.). The Julian date indicates that it was manufactured during October. Even though this carb "looks" original on the BOSS 429 engine it occupies, it can not be "original" for a 1969 model car when it was not manufactured until October 1986.


The List-2804 and List-2805 assemblies have wide possibilities for dates as they were a) used on several types of new cars, b) used for more than one model year, and c) used in racing also.

These two models were introduced as a running change during the 1963 model year run of 427 Galaxie 8V engines and were used through the 1967 model year. They were standard equipment on:
- part of the 1963 model year for Ford Galaxies with  427 8V engines
- 1964 model year Galaxie 427 8V engines
- 1965 model year Galaxie 427 8V engines
- 1966 model year CSX31xx 427 Cobras with 8V engines
- 1967 race season Group II 289 race engines in Shelby American Group II Mustang racers
- 1967 model year GT500s with 428 8V engines

There were lots of them installed on new engines over several years. They also seemed to be a popular over the counter offering at least through 1970. The only trick seems to be finding great cores of a particular date time frame with their original dated assembly tags intact.


« Last Edit: November 14, 2018, 06:17:53 PM by Dan Case »
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Dan Case
1964 Cobra owner since 1983, Cobra crazy since I saw my first one in the mid 1960s in Huntsville, AL.

[azdriver]

Now on Ebay....


https://www.ebay.com/itm/404462522574

[Drew Pojedinec]

This fella has been trying to sell this carb for two years.

An NOS carb with missing parts for $3000 is what it is.

[QuickSilverShelby]

This fella has been trying to sell this carb for two years.

An NOS carb with missing parts for $3000 is what it is.

What parts are missing?  I'm curious and would like to be educated.

QSS

[Coralsnake]

I dont see the little arm on the front bowl that opens the little rubber vent cover

[Special Ed]

 Good carb for restoration reference and the 2 parts missing are easy to find from holley as they sell many small parts. I. have bought many ford parts from this seller over the years and been to his shop in east colorado  several times over the years as he is a good guy to deal with  and his parts are not rust pitted in his dry area.