latest carburetor recommendation for 401?

[Guest musclecarfan65]

hi guys.

i just wanted to ask you what your lastest up-to-date recommendation would be when i replace the standard carburetor in my 401 rivi?

it should have an electric choke & an extreme good fuel economy. currently i am using a modified standard iron intake manifold.

i use my car mostly for cruising and not for the 1/4mls red-light dash so it does not have to have the highest cfm.

thanks for your thoughts,

dirk, germany.

[carbking]

The original Carter is virtually impossible to beat for either driveability or economy. One that might would be the original Rochester quadrajet from a 1966 401. Changing to this carburetor would mandate also changing the intake manifold.

Nothing else is close.

Jon.

[Guest 40series]

The edelbrock is a direct replacement but the same carb. Part no. 1406

[Bill Stoneberg]

Dirk,

I can get 16 mpg out of my 425 if I keep my foot out of it.

This with a bone stock engine. You can add an electric choke if that bothers you.

[RivNut]

Dirk,

In your original email, you say that you have a 401 powered Riv. That means it's either a '63 or a '65. That makes a difference when it comes to carbs. "40 Series" says that Edelbrock's #1406 is a direct replacement. It's not if when you take into consideration the linkage for the kickdown. The '63 needs mechanical linkage for the dynaflow, and the '65 needs provisions for hooking up the linkage to the TH400's electric kick-down switch. With the 1406, I had to use an aftermarket air cleaner because the 1406 has an air horn the same size as a Q-jet or a Holley. When I bought my '64 it had a 1406 on it. The first thing I did to get everything set to work properly was to buy a rebuilt stock Carter AFB. They both perform the same, but I now have all the proper fittings in all the right places and I now have a properly functioning kick down. If you have a '65, that kickdown switch also operates your switch pitch converter. Why have all the advantages of that switch pitch ST400 if you can't wire it up?

Contact Jon "Carb King" and see if he doesn't have the proper AFB for you, or get a kit from him and rebuild yours; it's not difficult.

Ed

[tim63riv]

Dirk,

The Edelbrock is not a direct replacement, the factory air cleaner housing will not fit on it, along with the linkage issues. I would suggest you rebuild your Carter or have someone else do it. Fuel economy is always going to be an issue with a 401 in a heavy car!

Tim

[Guest musclecarfan65]

thanks for your appreciated feedback on the '65 carb 401 topic. what i will do after reading all your comments (and also the talks i had in my specialist's garage) is to clean the old carb (spark plugs where looking good so there was no lean or rich mixture), adjust it and maybe add an electric choke i once received this from an american ebayer who used to be thrown out of the ROA (as far as i remember). will see if that thing works.

what i always tend to forget is that out rivi is a very heavy car with not the most outstanding aerodynamics :-).

[RivNut]

Dirk,

There's an article in the tech section of the ROA website that gives info on wiring an electric choke. It uses a 3 pronged oil pressure sending unit "in line" for 12V only when the car is running. The choke gets no 12V power during cranking or if the engine stalls; won't open too quickly.

Carter still manufactures an electric choke for the AFB. I got mine from Allstate carb and fuel injection in Central Islip, NY. http://www.allcarbs.com/shop.html.

Make sure you have the stainless steel gasket between the carb and the fiber gasket on the intake manifold. Otherwise the exhaust gases will corrode and eat through your aluminum based carb completely ruining it.

Ed

[carbking]

Give some serious thought about using an electric choke with your vehicle.

The problem with electric chokes is the timing. Electric chokes are set to go completely off after a certain time period (usually less than 2 minutes, some much less).

An older vehicle with automatic transmission REQUIRES some extra enrichment to the carburetors main metering circuit until the transmission fluid is warm. This is why the original chokes are keyed to the heat of the engine.

Why is this important? If you have a manual transmission and can thus slip the clutch, it isn't important. However, with the automatic, should the vehicle be driven when the temperature is below 50 degrees F (approximately 10 degrees C.), it is quite probable that the engine will stall at the first stop light AND NOT RESTART unless the operator allows the engine to warm at a high idle (with the operators foot on the footfeed) for 10~15 minutes before leaving the driveway.

This can be both embarrassing AND dangerous.

Once the engine is completely warm, then the issue is moot.

The most common reason for wishing to place an electric choke on an older vehicle is convenience if the heat tube in the manifold is burned through. A manual choke conversion is MUCH more reliable than the electric choke.

If the automatic has been replaced with one from the 1980's or newer, then the electric choke should not be a problem.

Jon.

[Bill Stoneberg]

Jon,

Thanks for the good information, I often wondered about that and now I know.

BTW, its great that you are on these forums and contribute your knowledge to help us all. Thanks

[Guest musclecarfan65]

that was really a great feedback because it shows me the way of best improvement of the carb - clean everything and leave it as it is :-) thnx to all of you. good to be a member of the ROA and here (of course :-) )

[Guest 40series]

I meant direct replacement as in it bolts on as the original AFB and requires no more ability than what you would need to possess to do the job. I wouldn't post it if I hadn't done it.