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Hey all Im new to the forum, just bought a 49 Standard 8 thats been sitting since 1984. Pretty much as barn find as you can get on the outside but the interior is still in one piece. On to the issue I have at the moment, the carb. So when I bought the car the carb had disappeared at some point over the past 4 decades and was no where to be found by the owner. According to what I have found the car is suppose to have a Carter WDO 644s carb, cool. As I am not really willing to pay out hundreds of dollars for a rebuilt one my question is what models of Carter carb will work on this 288? I see different WDO carbs but have no idea what the number means on these. I know the WDO has the fuel connection I need but whats the difference between a 644s and say a 502s? Are there any other models than WDO that work on these?

Buy a non rebuilt one and rebuild it yourself is the answer. It's really not too bad just be sure to ask questions if you're stuck.

An old carb + rebuild kit for it is typically about $100 combined if you know where to look.

To be honest I'm not super familiar with these so maybe they are super rare for some reason, but I doubt it. There are tons of bathtub car parts "float"ing around.

And

Its mainly the numbers that are throwing me for the loop. I know if we were talking Holley 650 or 750 we are talking about CFM and I can kinda judge on what is needed but I have never seen number sets like these.

I suspect the biggest difference between numbers would be in jet size and adjustments that were specified by the various mfgs engineering depts to be optimized for the engine it was going on.

The correct WDO carb core for your model Packard should be available relatively inexpensively from those on the forum with parts cars or some of our used vendors. If you are handy and a bit mechanically inclined rebuild kits are also easily found. You could probably do something like that for far less than the cost of a professionally done rebuild.

Another option which recently came on the market is a replacement universal 2 barrel carb from Daytona Parts. Daytona has been around for years and has done rebuilds for many of us. Their new carb may or may not need some kind of adapter to bolt to the manifold but from the description and the fact it is a new carb it might be worth looking into. I expect the price would be in the same neighborhood as a rebuilt original though.

Aside from the visual differences, probably the biggest downside to going with a universal carb is you would need to add a pushbutton to start the engine as the accelerator pedal carb start switch would no longer be there.

Ive been through a carb or two in my time. I have seen other WDO carbs online it just seems like the 644s is a harder unit to find secondhand without it being rebuilt by a company. And if the numbers were something like CFM or an identifiable parameter for performance then I could say ok for sure a 650s would work but not really smaller than that. Dont want to find a smoking deal on a hypothetical 250s just to find out it doesnt have enough cowbell to idle the motor. Also the accelerator switch is gone as well so have to either source one or do a button in the cab.

Thanks for the welcome humanpotatohybrid!

G'day dhart1977,

Besides HPH's let me add my own to PackaedInfo.

And, I invite you to include your '49 Standard Eight Packard in PackardInfo's Packard Vehicle Registry.

Dhart1977
A Carter 502S is a carburetor intended for a Hudson, with 1.187 main venturi diameter, and 1.25 throttle plate diameter. The 502 does have anti-percolation valves, but no starter switch or distributor vacuum port.

A Carter 644S is a carburetor intended for a Packard, with 1.125 (smaller) main venturi diameter, and 1.25 (equal) throttle plate diameter. The 644 does have anti-percolation valves, and both a starter switch and distributor vacuum port.

The diameter of the primary venturi is the same for both carburetors (11/32 inch). The external linkage differs between the two items.

Implication: Based on the larger main venturi size the Hudson carburetor would likely have a higher CFM rating. The distributor vacuum could be connected directly to the intake manifold, while an auxiliary starter switch would suffice. External linkage may (emphasis on vague) be swapped. The entire throttle shaft would need to be swapped, and that’s an overhaul step that I for one avoid. New linkage from the firewall to the carburetor would likely solve the incompatibility.

With the difference in the main venturi size avoid a comparison between the jet/rod sizes. At any given airflow a larger main venturi will result in less airflow through the primary venturi, and thus less suction on the discharge nozzle. To achieve the same fuel flow with less suction the main jet / metering rod flow area must increase. The Hudson 502 main jet is 0.086 inch diameter, with a power step rod diameter of 0.044 inch. The Packard 644 main jet is 0.0846 inch diameter, with a power step rod diameter of 0.045 inch. Resulting in a Hudson fuel flow area 0.00858 in**2, and a Packard fuel flow area 0.00806 in**2 (both on the power step). The difference in fuel flow area is to accommodate (likely at constant air/fuel ratio) the main venturi size change . . . a 502 equipped engine will not likely run any ‘richer’ or ‘leaner’ than the same engine with a 644 installed.

dp

The carb #s have nothing to do with CFM and chiefly denote which metering rods and jets they have.

The Carter WGD was used on the 288 engines in later years. I find they are easier to build than the WDO models with less fussy adjustments. I have them on 4 different Packards and find they give very little trouble. So happens, I built two of them today for a customer.

Anyway, that is what I would recommend, and they will bolt right on and are equipped with the starter switch. I can sell you a good rebuildable one for $75 shipped to your door.

Otherwise, I am pretty sure I have a WDO that came off either a 288 or a 327 so will work on your car. Same money