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I can offer no advice on which way to go, I went with having mine rebuilt by Daytona which was considerably more expensive than any number you note. The results were outstanding in every way.

But BH's comment from a few posts back really deserves some added emphasis. The Rochesters used on the dual 4-bbl Caribbeans were not the same as the single Rochester used on the 400 and Patrician, were not the same front to rear, and were not the same 55 to 56. I'd make a careful assessment of just which ones you have, and if you do an exchange for rebuilts, which ones you'll be receiving back. The carb #s and differences between front and back and 55 and 56 can be found in the service letters and TSBs.

AL -

The 4GCs are one of the easiest carbs I ever had to rebuild, and the kits from Daytona should have all the parts required for a typical rebuiid. However, I'm sure that your present job doesn't leave you much time.

Clearly, you need to sublet the work. However, I strongly discourage you from purchasing an off-the-shelf, rebuilt/exchange unit, and that's regardless of my predisposition WRT inheriting someone ele's problems.

Unless your carbs have the CORRECT tags still on them or you can identify the exact (supplier's) model number with certainty, you should to send them off to a rebuild shop who really knows 4GCs. Daytona also rebuilds and has some atypical parts for their internal use only.

I have heard of this Daytona mentioned before, but what is the full name. Daytona ??????? I did google just daytona and came up with chevy, dodge, ford, but no Packard and nothing relating to carbs.

Sorry, they've been around so long that I thought it was common knowledge. Here it is (linked):

Daytona Parts Company

O.K. I may dumb, stupid, blind or dense or all of the previous, but I just gave those carbs a good once over and I can find no numbers on them anywhere. Any idea where they might be. I think someone mentioned once somewhere a metal tag on them but I do not see those either.

Yes, the carburetor numbers were on a triangular stamped brass tag under one of the cover screws. It's a shame if the tags are missing, happens all to often. Without them, it's still possible to identify them I guess but will be difficult. Among the many differences, the 56 twin Rochesters can be identified by a pair of air-velocity controlled butterly valves in the secondaries, just above the conventional throttle plate, which the 55s didn't have. The 55s have a fuel bowl vent controlled by a linkage actuated valve, the 56s don't. And the rear carb doesn't have an idle speed screw adjustment. I believe the 55s have a screw plug in the fuel bowl wall for determining the float level, the 56s don't. There are other differences, in jet sizes, etc.; you can find most of the specifics in the service letters, TSBs and part book.

PS - another difference, at least for 1955, not sure about 1956. The front carburetor has a 3-step fast idle cam, the rear but a single. See the June 1955 Service Counselor (Vol 29, #6) for specifics on the 1955 Caribbean carbs, I'm sure similar data is available for the 1956 versions. Here's the numbers: 1955, 7008230 for the front, 7008231 for the rear; for 1956, 7009600 for the front, 7009601 for the rear.

Well I guess I may be in a bit of trouble because I have gone thru all of my old pictures and I cannot find one that show the brass tag.

Start by listing the features mentioned above that you have or don't have. We can go from there.

If I sent them to Daytona would they be able to make the determination??????.

I'm sure Daytona could identify the carbs, but a little preliminary leg work is in order, first.

A pic of your engine, from much earlier in this thread, seems to show the correct choke housing covers and heat tube - even a shield - as used with the factory-style 2x4 set-up. If the conversion work was done when the car was new, and parts were plentiful, I'd like to thnk that carbs designed for a 2x4 set-up were use, but let's not assume too much.

Next, because the 56 Caribbean's 2x4 set-up was designed with a 374 engine, and your car has a 352, I wonder if the original owner went so far as to select the 55 Carib carbs, which were designed with a 352 engine in mind. Even the still-born Jet Streak package specified the 55 dual 4GCs for the 56J Golden Hawk, which also used the 352 Packard V8.

First, let's determine whether the units on your car are 55 or 56 models. The easiest way to do that - whether single or dual 4GC - is to check for the presence of sight plugs in the driver's side of the fuel bowl - as I've indicated in the pic below (borrowed from SC Vol. 29, No. 2). These plugs are NOT used on 56 models.

Then, you can look at some other clues to see if they are genuine front and rear carbs - like the idle speed stop screw and the fast idle cam on the respective throttle body assemblies (as described in SC Vol. 29, No. 6). According to the parts book, there's no difference in those details between 55/56 2x4 applications - just front vs. rear.

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