1966 390 2 BARREL CARBURATOR!

[SIXTY SIX BIRD]

Just noticed I have a 2 barrel carburetor on my 1966 390 engine (see image). I have no history on the cars mechanical past. The kick-down linkage is also missing so the car doesn't take off when the pedal is to the floor.

My questions: Can I keep the 2 barrel version, replace it or rebuild it and get better performance? Can I get a kick-down linkage assembly anywhere and if so, where? If not, is it necessary to have the linkage just leisurely driving of the car? The engine may be from another vehicle or perhaps just the manifold and carburetor were replaced; not sure. Where is the info on this carb for a replacement or re-build? It is marked Motorcraft and may have been re-built at one time already.

Any advice, opinions or answers will be appreciated. Thanks!

[georgemii]

That’s the Motorcraft 2100 series carb.
Widely used; lots of parts and support available.

FWIW - my (‘65 390) has one; installed by previous owner.
I’m happy with mine, but I’m not an “in a hurry” kinda driver.
Fuel mileage may be marginally better than the 4 barrel.

When your carb was installed, the intake manifold was changed, obviously.
This makes installation of the kick-down linkage a different ball game.
I have a new kick-down rod; bought commercially for 390 with MX transmission.
I think it’s the correct shape, but I have not succeeded with installation;
stymied by the throttle/bellcrank hardware on the firewall.

Hope this helps.

[64ZCODE]

That’s the Motorcraft 2100 series carb.
Widely used; lots of parts and support available.

FWIW - my (‘65 390) has one; installed by previous owner.
I’m happy with mine, but I’m not an “in a hurry” kinda driver.
Fuel mileage may be marginally better than the 4 barrel.

When your carb was installed, the intake manifold was changed, obviously.
This makes installation of the kick-down linkage a different ball game.
I have a new kick-down rod; bought commercially for 390 with MX transmission.
I think it’s the correct shape, but I have not succeeded with installation;
stymied by the throttle/bellcrank hardware on the firewall.

Hope this helps.

My understanding is that the largest Motorcraft 2100 carb was 425 cfm. Seems way too small for such a large engine. Sixty Six Bird could install a larger 2 barrel carb, say 500 or 550 cfm, and the performance improvement would be noticeable without much sacrifice of fuel mileage.

[vince]

Nice picture. If I read the casting number correctly you have '65 intake (C5xxx). Perhaps a previous owner swapped a whole engine in. Not critical at this point but something you might keep in mind as you assemble parts or make other decisions.

[Alan H. Tast]

The carb in the photo is post-'66, possibly an Autolite/Motorcraft 2150 (?) , and most likely 1970s vintage based on the rounded top cover and the power valve (?) in the top of the carb behind the carb throat. Replacing the original 4-barrels with a 2-barrel was common during the mid-'70s "gas crisis" as people look for simple ways to cut back on fuel consumption.

What is the full engineering number on the intake, and is it a 2-barrel or a 4-barrel intake with an adapter plate for the 2-barrel?

[64ZCODE]

The carb in the photo is post-'66, possibly an Autolite/Motorcraft 2150 (?) , and most likely 1970s vintage based on the rounded top cover and the power valve (?) in the top of the carb behind the carb throat. Replacing the original 4-barrels with a 2-barrel was common during the mid-'70s "gas crisis" as people look for simple ways to cut back on fuel consumption.

What is the full engineering number on the intake, and is it a 2-barrel or a 4-barrel intake with an adapter plate for the 2-barrel?

Hey Alan, you raised a point I'm interested in, which is how well does the 4 barrel carb to 2 barrel intake manifold adapter work? I have another car with a 351W and 2 barrel intake manifold that I want to convert to 4 barrel carb, and I might want to try the adapter approach first rather than just replacing the manifold with a 4 barrel version.

Doug

[scumdog]

The carb in the photo is post-'66, possibly an Autolite/Motorcraft 2150 (?) , and most likely 1970s vintage based on the rounded top cover and the power valve (?) in the top of the carb behind the carb throat. Replacing the original 4-barrels with a 2-barrel was common during the mid-'70s "gas crisis" as people look for simple ways to cut back on fuel consumption.

What is the full engineering number on the intake, and is it a 2-barrel or a 4-barrel intake with an adapter plate for the 2-barrel?

Hey Alan, you raised a point I'm interested in, which is how well does the 4 barrel carb to 2 barrel intake manifold adapter work? I have another car with a 351W and 2 barrel intake manifold that I want to convert to 4 barrel carb, and I might want to try the adapter approach first rather than just replacing the manifold with a 4 barrel version.

Doug

In my experience you would by well ahead sourcing a 4bbl manifold, adapters are a poor inefficient compromise.

A 4bbl intake and 600cfm Holley would be my pick.

[64ZCODE]

The carb in the photo is post-'66, possibly an Autolite/Motorcraft 2150 (?) , and most likely 1970s vintage based on the rounded top cover and the power valve (?) in the top of the carb behind the carb throat. Replacing the original 4-barrels with a 2-barrel was common during the mid-'70s "gas crisis" as people look for simple ways to cut back on fuel consumption.

What is the full engineering number on the intake, and is it a 2-barrel or a 4-barrel intake with an adapter plate for the 2-barrel?

Hey Alan, you raised a point I'm interested in, which is how well does the 4 barrel carb to 2 barrel intake manifold adapter work? I have another car with a 351W and 2 barrel intake manifold that I want to convert to 4 barrel carb, and I might want to try the adapter approach first rather than just replacing the manifold with a 4 barrel version.

Doug

In my experience you would by well ahead sourcing a 4bbl manifold, adapters are a poor inefficient compromise.

A 4bbl intake and 600cfm Holley would be my pick.

For sure! And add to that GT40 heads, a camshaft and headers. Just trying to ease into this so my head doesn't explode

[Alan H. Tast]

I thought GT40 heads were a 5.0L/small block Ford thing vs FE-series 352-390-428, etc.

[64ZCODE]

I think you're right, Alan. The engine I was referring to in my question to you is a 351W small block in my '69 Galaxie. It has a 2 barrel carb and manifold and I'm considering next steps to goose it up a bit. Doug

[JamesR]

My '65 T-Bird also has a 390 with a 2 bbl in it. In my case, the original engine had been replaced with a 390 out of a more mundane car of later vintage - possibly a full sized Mercury from about 1967. The carb was likely original to the replacement engine.

You can determine whether the engine in your car is a Thunderbird engine by looking at the casting # on the block/heads. On my car, that was located on the passenger side of the engine under the exhaust manifold. The casting number was very hard to see, in my case. I had to use a mirror and a flashlight, and had to read the number upside down and backwards, as I recall. There are places online that tell you what you've got. I think this site gives accurate info, as I recall:
https://fordclassics.com/part-numbers

From what I've been able to gather, my replacement engine is about 270 hp as compared to 300 hp of the original engine. Enough to make a noticeable difference? Probably, but not likely enough to turn my 4500 pound car into a hot rod by putting a 4bbl back on it, so I'm leaving it as is (since the current engine runs fine.)

Oh, BTW, I just remembered: If your engine is not original, it can be difficult to determine from external cues whether it's a 390 or a smaller displacement FE like a 352 or 360. The only sure way to tell what it is is to measure the stroke, which is fairly easily done by removing a spark plug and cranking the engine SLOWLY (preferably by hand.) A plastic dowel in the spark plug hole will move up and down with the piston. A 390 has a 3.7 inch stroke I think, and the 360 and 352 have a 3.5 inch stroke. OF course '66's also had 428's but I don't know what the stroke of those were.

[SIXTY SIX BIRD]

Thanks to everyone for your assistance!

[jtschug]

A Ford 390 FE has a 3.78" stroke, same as the 427 but with an iron crank instead of forged steel used in the 427.

A 428 FE has a 3.98" stroke, a bit less than 1/4" difference between the two.