Carter AFB 4120S

[robodhran]

Hi - I do have a a 1967 273 Commando engine with the Carter AFB 4120S Carburetor that will go into a 1966 Plymouth Barracuda with 4-speed manual transmission.

The carburetor was designed for a automatic transmission (as the book says). In fact the carb-number for a manual transmission should be correctly AFB 4119S.

There are some differences between the two carbs:
Vacuum Kick (drill size) 4119S= 1/8" - 4120S #42
Fast Idle Speed (r.p.m) 4119S= 625* - 4120S= 700*

Does it cause problems to use a automatic-transmission carb in a 4-speed manual car?

Thanks a lot.

 

[moe7404]

my 1967 dodge factory manual shows for the 273.
1. AFB - 4294s manual trans
2. pri jet .089,,,,sec jet .073,,,,idle jet #66-.033
3. AFB-4295 auto trans
4. pri jet .089,,,,sec jet .073,,,,,idle jet #66-.033......NOTE; idle jet is NOT removable.
5. both carbs. THROTTLE BORE PRI,,,1-7/16",,,,,SEC,,,,1-9/16"
6. both carbs,,,MAIN VENTURI PRI,,,,,1-1/16".......SEC.....1- 1/4"
7. ACC PUMP ADJUSTMENT. 7/16"
these are the most important specs. i think the spec you listed if a little off is not that big of deal. . i have ran a float level of 5/16 that worked well. but i would not go higher. 7/32 is what is called out.

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[robodhran]

Well fine, thanks a lot!

Is there any preffered place to send carter-carbs to for rebuilding in USA?

 

[moe7404]

they are easy to do. if you have a local mopar club check with them. or maybe an internet howto. some hints. 1. clean work table. 2. tubing wrenchs. no rounded fittings for us. and NO hose for fuel line. 3. some small cans to hold small parts. 4. separate parts by type. some parts can go into the soup, some cant. 5. do NOT remove jets if you dont have to, and do NOT force them. if they are stuck there is a trick to get them out. and with some one to guide you, you should be fine. 6. and in middle at the front and back is a screw. of different lengths front to back. DO be sure the screws go back in where they came from. the screws on the outer edges are all the same.