3259 differences

[Tomdeg]

I have 2 different 3259 carbs. I realize neither of these are SA assembly line units, but what are the differences based on the numbers?

Thanks,
Tom

[Bob Gaines]

Both are later reissue carbs. The one missing the S2MS is the older of the two before a Ford vender got Holley to add the Ford/Shelby engineering number.  The newer one has a date code that is probably 1991 or 2001 . The older plain one is probably from 1981 or 91.

[Bob Gaines]

On reflection I thought I should explain better my thought process. The service replacement parts had the S2MS number until the early 70's at which time the S2MS number was dropped leaving just the list number and date code. The look of gold chromate finish on the picture carb with the S2MS matches that of the look of the later reissue carbs that Carls Ford ,Branda etc. started to handle compared to period NOS that I have seen and had. That is how I came up with the sequence of which came first in this specific case .  Just my opinion.

[Tomdeg]

Thanks Bob, internally they are both the same (jets, nozzles, etc?)

[Bob Gaines]

Thanks Bob, internally they are both the same (jets, nozzles, etc?)

They should be but Holley would update things as they saw fit so the jets may be different etc. Outside difference also For example the main body casting is visibly different on a later made carbs compared to their 60's made counterpart.

[gt350hr]

 
+1 great information Bob. Even the float bowls have changed a bit on the latest ones.