What is the correct carb for a 1966 GT350? Didn't they have at least two different carburetors throughout the production run?
Thanks, I thought i had read that somewhere as well. The Holley 715 is 715 cfm, or cubic feet per minute, right? So is that what it is known as or does it have a model number? Is it the Holley 3259?
note: date code (713) for the carb above is for a '67 GT-350, other numbers are the same for the '66 GT-350 Z.
Great photos! Thank you! How do you decipher the date codes? Was there different codes that correspond to the month of production or something like that?
Early 66 cars had Holleys without the S2MS number, only 3259 and date code. For example 6S923 has one dated 581. Automatic cars from 6S801 has Autolites. This according to an letter from SA which I have a copy of. Texas Swede
year/ month/week so for example 713= 67/Jan/3rd week the second code (month) is always single digit so after numeric 1-0 run out in Oct they go to A, B for Nov, Dec.
first number is the year of manufacture of the carb next number is the month of manufacture of the carb (Nov is "A", Dec is "B") last number is the week of the month. if the carb has a 4 digit date code it is not made is the 1960's and is worth less than a 60's made Holley 715. Four digit date date: first number is the year made, last three digits are the day of the year. ex: 7122 = carb made in 1977 (or 1987, or 1997, etc) and the 122nd day of the year. Z.
We know the '66 carb was a S2MS 9510-A, what were the Shelby and Ford part numbers the the '65 Holley carb?
For the ones I have seen there is no Ford or Shelby numbers, only the 3259 holley list number and a 3 digit date code. Jay
Jay, Actually, I was asking if anyone has seen a listing for the original in a parts catalog. I know that there are no other stampings on the carburetors than the list number and the date code. Thanks.
Roy, Sorry, I misunderstood the question. FWIW, I went through my Holley numerical listing catalog and in the "Vehicle Mfg part number" column they show S2MS-9510A for the 3259-1 and nothing for the 3259. Shelby may have had a P/N for it, but Holley does not show anything in the catalog I have. Jay
Based on the HOLLEY CARBURETOR COMPANY FORM NO. F-279 ISSUE NO. 2 (6-66) 1964-66 FORD V-8 HI-PERFORMANCE & DUAL CARB INSTALLATION 289, 390 & 427 CUBIC INCH ENGINE in June 1966 there were at that time three former versions of the R-3259 series and a fourth as the service part at the time. R-3259A with C5AZ-9510-A for a Ford number. The data sheets also have a R-3259AAS, R-3259-1A, and a R-3259-1AAS as the then current service part. From all the carburetors I worked on for people in the 1970s and 1980s the suffixes A, AAS, 1A, and 1AAS were all revision levels in the complete assemblies. In other words just like whole cars the exact content of each series was in some way different at different subsequent times. The biggest change was the addition of a killer bleed to the secondary opening vacuum circuit. I have seen 3259s modified to work like a 3259-1 and visa versa. In one modification you drill a hole and the other you plug a hole.
I've run across this part number in the past as well. Interesting that it was a C5AZ number. That would normally indicate a Galaxy part. But in the case of Shelby parts, anything is possible. Thanks, rr64 for confirming. The information is much appreciated. Yup, revision levels are the only way a company can maintain configuration control of their product. And without copies of the production drawings, it is all most impossible to know exactly what all the changes were.
The first version (both December 1964 runs) of R-3259s were just like the last runs of the R-2668 with fuel bowls and transfer tube changes. I have compared casting and engineering numbers (Holley numbers) between the two series. The R-3259s were not the first ones with the new 'center inlet' (a.k.a. LeMans) bowls. Perhaps the R-3259s were originally intended to replace the R-2668 in big block Fords and just got cherry picked from the corporate parts selection for GT350s?
