Know Your Ford Carburetor

Ford Carburetor ID

Episode 123 Manic Mechanic

Autolite 2100 ID 1960-1974

All information is listed in the description below.

1. What sizes? There were 8 different venture sizes for the 2 barrel 2100.
.98 @190 cfm
1.01 @245 cfm
1.02 @ 240 cfm
1.08 @287 cfm
1.14 @ 300 cfm
1.21 @ 351 cfm
1.23 @ 356 cfm
1.33 @ 424 cfm

Autolite 4100
1.08 @ 480 cfm
1.12 @ 600 cfm
1.19 @ 669 cfm

2. In order to know what size venturi you have look on the drivers side of the float bowl. There will be a set of numbers that corispond to the venturi size we just talked abut. Thus yu can know what the cfm of the carburetor is.

Tech tip: CFM stands for cubic feet per minute and lets you now how muchg air and fuel will pass the veturis when the car is running.

3. The carb tag ia and was the most detailed part of the carburetor info. If it has the carburetor tag it will list the Decade, year, model of car, and group (Carburetors are Group F) the leter after that denotes what the use was, typically it was for manual or automatic. Below that on the tag is the change level then the date year is first, followed by month (There is no I in the date coding system as it could be confussed with a 1 then day.

IF the tag is missing the carburetor info is on the drivers side front foot of the carb. But it will lack the date code.

4. In stock configureation, at 4,000 rpm at 90 percent volmetric efficency, the Autolite 1.14 venturi carburetor will perform very well. But it won’t get the kind of miulage that a 4100 autolite can. Simply put, a 4V carburetor will get better gas mileage if you don’t dploy the secondaries because the primaries are smaller. The chart I am showing is available on our website at the url below.

289-302 go with 1.08 primary. (this in the 4100 is 480 cfm) and will net you better milage.

Our 260 has a 240 primary.

5. The Autolite 4100 has some sticky points.
• No PCV port on the carb. The only port is on the spacer.
• Many aftermarket intakes will not support the 4100 spacer due to the base plate confifureaton.
• Thre manual shift 1.08 carbs are expensive since they are for the HiPo 289 typically.
• The 1.19 venturi is ultra rare and was only used on the 383 “high torque Mercury engine in 1958.

Issues on both the 4100 and 2100
• Jets on both carburetors are usually specific Ford jets but can be obtained from places like Mikes Carburetor. Early carburetors up intol 1966 ish used a jet the same size as Holley.
• Power valves are common to Holley but some caps can interfier with the power valve.
• The throttle shafts can be worn and might exibit issues will weird idle charicteristics.

Carburetor Spacer Kit: C3OZ-9A589C

[ericlindahl]

I’m running a 2100 on my Torino right now but was looking at upgrading my setup to a 4100 so this video was perfect for me. I really appreciate it.

[TheVenom]

After years of watching YouTube, I just found your channel. I am a Ford fanatic!! I've got an 80 Mustang Coupe with a 351w swap. I just subscribed and I'm about to binge watch your videos I'd love to see a video on the 4300, I had no idea they even existed...

[farmerjim-fat-man-do]

Good details in the video. Most people throw their old auto lite on a shelf for a Holley. Other than the issue with stumble in hard corner I prefer them for a daily driven vehicle. The annular boosters on the autolite are great at atomizing fuel and result in a very snappy throttle response. The autolite boosters are far superior to any stock holley booster. A few more details some people don’t know. The accelerator pump and power valve are Holley parts even after they switched to Ford jets. The Venturi size is only half the story. The boosters also sized differently. They are stamped with a letter code. Ford used different sized boosters and jet combinations to dial in a carb for the vehicle and engine it was built for. I haven’t found a good source for decoding the boosters.

I am one of the lucky ones that have a 4100 for a manual shift mustang. It’s going to look nice on my engine once I swap it over to the top loader laying in the corner of my shop.

[Neddles]

Great clip. A lot of useful info, thanks a bunch!

[HunterNapier]

Also yes, stuff like this is priceless. It's hard to find info often and for younger guys that are getting into old cars, it gets tougher every year.

[Paulie]

Nothing like knowing your carb and Jeff is the one that can bring it to you....

[greenbean]

C3AF AU 1.12 Venturi sitting on the shelf. Love the channel!

[cutworm]

I installed one on my 84 Mustang GT. Better mileage but cut power. I have witnessed Holly's burn cars pretty often. God bless

[cagleoutdoors]

Thankyou man I really love your videos and needed a video just like this god bless

[A_Litre_of_Farva]

Awesome video! I'd love to see a video focusing on the Ford/Motocraft 2100/2150 - weak points of them, what to watch out for when rebuilding, et cetera.

[slick-pxpq]

Great info. I went and looked at the 2100 from a 352 that is now a 445 and there's no tag. All the info, including the date code is stamped on the foot(1965).

[adamwnichols]

Thanks for the info! I would love a video on how to tune one of these carbs!!

[ajw]

I have one of the 4 barrels I bought at a garage sale for $20. I will be checking it to see which one it is now. Thanks!

[DBlue]

I have one of those, was on my ‘69 galaxie convertible 390 fe. Had the motor redone and managed to find a ‘69 cobra jet Holley 735 cfm.

[fenatic]

I took the 4V 4100 off of my 65 352 with the 1.12 Venturi and it was perfect for the 289 hi po clone from a 302 we biuilt with the Voodoo cam and a C4 for my father in laws 65 Fastback. and hipo manifolds and it was fantastic!

[fenatic]

My 69 Galaxie had a 1.33 Venturi 2V it was the premium fuel IP. It was really great!

[OlysGarage]

These are fantastic Carbs. Definitely familiar with the hard corner stumbles (very noticably right turns...lol) I think if they had a more open aftermarket support they would be a real contender. A lot of people just don't know where to get parts or tuning pieces and that drives them away. The Summit 4bbl carb very closely mimmicks a 4100 with more Holley design and parts.(was originally a Holley product to begin with) I hear good things about them.

[jimjordan]

Very informative video! Without some of the minutia, some things are just mysterious.

[mercman]

I have a 1963 4100 with 1.18 jets. The code for the carb is C3AF. It's on a 390 CI w/Cruise-o-matic transmission. And yes it can be finicky! :)

[michaelwelch]

They made a hipo 289 for a auto it was a 64 mercury comet 289 225 horse c-4 auto. It had 1.12" plus a auto choke.