How To Tell The Differences Between Imperial Carburetors


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Tips from Rodger:

I'll start with 1959. With this year MoPar introduced the 413 in the Imperial (and Chrysler) line. For the Imperials they had only an engine and an carb. (For the Chryslers they had more). As time went on the 413 showed up in the ...lesser MoPar line up, but with more horse power. As the 413 the engine stayed in the cars until 1965. (In the mean-time in the lower end MoPars they bored the engine out to 426 cubic inches). Starting with the 1966 year the Imperial engine became the 440 ( the older 413 just bored out again ).

The intake manifold is the same on all 413's, 426's and all 440's from 1959 until 1966. Starting with the 1967 440 the intake manifold was improved.

From the start in 1959 until 1963 the carburetors are basically the same carburetor. Starting in 1964 the carburetor was changed in the manner the lever was controlled. This style of lever operation is now present on all carburetors. The 1964 to 1966 carburetor is the same size and operating manner.

What this means is that from 1959 until 1966 one may put a carburetor on any engine for they all fit the same. If you cross the 1963 to 1964 line you must modify the lever to make it work, but it fits to the intake manifold. The same 1959 to 1966 rule also applies to the air cleaner housing fitting to the carburetor.

Starting with the 1967 440 the intake manifold carburetor base was changed in size. And the carburetor to the air cleaner housing base size. Also starting in 1967 some Holly's were used on some engines. And that was the way it was until the Thermoquad carburetor was used for smog fighting.

For the people who have come to stage of needing to rebuild their carburetor and don't have the funds to keep the engine department 100% correct for the year, they can "junk yard shop" from 1959 to 1970. Or if you have a 413 you can find a 1969 440 intake manifold (which has better breathing) and install it on that Imperial of yours with the six way seats. Or you can install the 440 engine in your 1959 Crown engine bay and keep the original 413 intake manifold and carburetor.

All of this has been said before and before. This is just a repeated story. I used 1959 to 1970 'cause it is hard to tell if there has been some parts swapping.

Question from Nigel (1929):

Can anyone tell me what sort, make and type of Carburettor the 1929 L*80 Imperial had?

When I got my car it had been off the road for best part of 40 years, the carb which it had is wrong...too small for a start.

I had planned to use twin S U's and make a new exhaust manifold...however I know realise that there just isnt the space under then bonnet (hood??) to do i now have a rebuilt engine and no carb.

Reply from Bill:

The 1929 Chrysler Imperial L*80 came with an updraft Stromberg UX4 carburetor.

No idea what other cars used that carburetor, though.

Question from Joran (1960 - 1965):

Do Imperials between 1960 and 1965 with 413cid engine ever have an optional 2x4 barrel carburator, or some special edition?


From Bill:

Not available originally, but if you've found one with such equipment, sounds like a cool car to have, and if you are planning to do it yourself, sounds like a great project.

We have formed a local Mopar club (South Central Indiana Mopar Club) and have a cruise-in every other Thursday night. Night before last, a gentleman arrived with a very nice '62 Dart 440, black with red interior, into which he had installed a big block with long rams. The bottom of the right hand ram underneath the carb mounting area touched the inner fender, which he had not modified, at least not yet, and the other side had about 1" of clearance to the inner fender. I suspect the Imperial would have plenty of room though for the long rams, or an original or repro cross ram will bolt on a regular 440 although with hampered flow due to severe port mismatch, or how about the new cross ram version from Rick Allison, A&A transmission, which is finished with 440-sized ports. Of course there's always the inline 2X4 manifolds.

From Kenyon:

The carb or engine was probably blown and the person went to the junkyard or the parts store and they didn't have the correct part. Since Chrysler parts interchange so well, they used what was at hand. I ran into a 1965 convertible that had a 440 with a 2-bbl carb. They just replaced the engine when it wore out. Owner said she got great gas mileage and drove it everywhere.

Question from Don (1968):

My '68 Crown currently has a Holley 4 Bbl on it. Everything looks like it's connected correctly. Was this carb available on a '68 Imperial or was the Carter replaced sometime in it's life?


From Dale:

To answer your question, your Imperial could have come from the factory with either the Carter or the Holley. I know of cars that were built with either unit. Others on the list may have a better/technical build knowledge of how Chrysler decided what cars received which carberator.

From Dick:

Most (maybe all?) California cars came with the Carter AVS in 1968, as I do not believe the Holley was approved for California smog rules. However, in the less fortunate areas of the country, Holleys were used in a sort of random mix with the Carters - whatever was on the shelf, I suppose.

Question from Roy:

How do you tell the difference between AFB and AVS carburetors?

Reply from Robb:

The best place to find the correct carburetor number for ones car is by looking in the year appropriate Factory Service Manual. This means one would have to go to the fuel system section and see which is used for that application.  If you have a 6125S on your Imperial when you should have a4966S, then someone must have made a swap.  All 440's carburetors are 4966S and it is a AVS.  On my '71, it came with 4971S AND a 4970S Carter AFBs as it was an automatic transmission vehicle.

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