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Discussion Starter · #1 ·
My 67 has a stock 289 that I installed a Weiand Stealth Intake and a Holley 4160 carb.

I have an opportunity to pickup an Autolite 4100 carb at a good price. I don't know much about these carbs other than they are great carbs and about 500cfm. I believe the 500cfm carb will work better with my mostly stock 289 as I am looking for a little more low end torque. My 67 is more of a cruiser so I don't wind it up to high RPMs. . A few questions for anyone that has experience with the 4100:

1. I see the Autolite 4100 comes with either 1.08 and 1.12 venturis?
2. Are these carbs fairly easy to rebuild and are rebuild kits available? I have rebuilt the stock Autolite 2100 a few times when I had the stock intake but that was many moons ago.
3. Will the Autolite 4100 fit on the Weiand Stealth intake?
 

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My 67 has a stock 289 that I installed a Weiand Stealth Intake and a Holley 4160 carb.

I have an opportunity to pickup an Autolite 4100 carb at a good price. I don't know much about these carbs other than they are great carbs and about 500cfm. I believe the 500cfm carb will work better with my mostly stock 289 as I am looking for a little more low end torque. My 67 is more of a cruiser so I don't wind it up to high RPMs. . A few questions for anyone that has experience with the 4100:

1. I see the Autolite 4100 comes with either 1.08 and 1.12 venturis?
2. Are these carbs fairly easy to rebuild and are rebuild kits available? I have rebuilt the stock Autolite 2100 a few times when I had the stock intake but that was many moons ago.
3. Will the Autolite 4100 fit on the Weiand Stealth intake?
We've covered these questions quite a few times on here.
1.08 is about the high 400's in flow and the pricier. The 1.12 is closer to the 540's and GENERALLY is considered a 390 cid carb.
(the exception being the 289HP's 1.12, which was calibrated specifically for the smaller engine)
4100's are easy to rebuild. I did my first rebuild back when I was in high school in the 70's.
On many aftermarket units like the Stealth, the narrow manifold "footprint" where the carb mounts means that more often than not
you need a spacer or plate so that you can avoid leaks between the carb's base and the manifold.

Gas Auto part Metal Circle Rim
 
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The 4100 is a great carb and easy to rebuild and maintain. The 1.08 is perfect for a stock to mild 289, but the 1.12 is no more overkill than the commonly-substituted 600 cfm aftermarket carbs. You can always swap jets to dial it in. If you can, get the factory 1" spacer with PVC port on the back with it, or one of the reproduction ones. Enjoy!
 

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The 4100 is a great carb and easy to rebuild and maintain. The 1.08 is perfect for a stock to mild 289, but the 1.12 is no more overkill than the commonly-substituted 600 cfm aftermarket carbs. You can always swap jets to dial it in. If you can, get the factory 1" spacer with PVC port on the back with it, or one of the reproduction ones. Enjoy!
You can't merely swap jets on a 1.12 to "dial it in" for a 289/302. It'll never idle right without addressing the primary booster and the
fact that most of those are calibrated for 390's and such.
 
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I've run a 1.08 and a 1.12. Your mileage may vary. Pun intended, I guess. @GT289 is likely correct in that. My engine was / is modified and I had no issues.
 
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There were some 1.12 carbs used on stock 289s. The 64 Mercury Comet comes to mind. A 1.08 will generally be easier to tune though Since it has boosters optimized for the SBF.
 

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Discussion Starter · #7 ·
Thanks everyone ;)

I'll check in getting the factory spacer with the PCV port. The Summit M08500VS 500cfm carb might be a better option. I've read its a very close design to the Autolite 4100. Unfortunately, its on backorder until February 2022 :(
 

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There were some 1.12 carbs used on stock 289s. The 64 Mercury Comet comes to mind.
Although true, we're now in the realm of the super rare and esoteric. There are roughly 4-6 different part numbers for early Autolite carbs
from the 63/64 time frame, which are 1.12 venturi and unique as they weren't installed on 289 K's and had automatic chokes.
(The C4OF-AL has similar weirdness in that it's a 1.12 and came as either an automatic choke or manual choke model..... and was used
on 289 hipos)
ALL of those weird carbs have primary boosters with either an outright K code mixture calibration (and the matching M or MA stamped codes
on them) or they have primary boosters with K code-like calibrations (and different ID's stamped on them that I'm not listing here).
 

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Although true, we're now in the realm of the super rare and esoteric. There are roughly 4-6 different part numbers for early Autolite carbs
from the 63/64 time frame, which are 1.12 venturi and unique as they weren't installed on 289 K's and had automatic chokes.
(The C4OF-AL has similar weirdness in that it's a 1.12 and came as either an automatic choke or manual choke model..... and was used
on 289 hipos)
ALL of those weird carbs have primary boosters with either an outright K code mixture calibration (and the matching M or MA stamped codes
on them) or they have primary boosters with K code-like calibrations (and different ID's stamped on them that I'm not listing here).
Interesting. I recently saw a post from a guy who was considering buying a 1.12 from a 64 Comet. I might inquire more about it.
 

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I’m rebuilding a 1.12 C4AF-DJ. KA on primary booster, AB (or BA?) on the secondary. No idea how it will run, but gonna try it with an Edelbrock RPM intake. Only question is if I’m putting it on my unknown 302, or picking up a GT40P motor for a winter project. :)
 

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The stock 4v 1" spacer will not seal on most artermarket (narrow) manifolds.
one for a boss 302 will work but i have run across some repos that leak where the fitting goes in the spacer


ken
 

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Discussion Starter · #13 ·
I'm going to go with the Summit M08500VS 500cfm carb. By the time I purchase a 4100, rebuild kit and spacer, I could get the Summit carb that is very similar to the 4100 and will be a direct bolt on to the Weiand Stealth intake.
 

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I’m rebuilding a 1.12 C4AF-DJ. KA on primary booster, AB (or BA?) on the secondary. No idea how it will run, but gonna try it with an Edelbrock RPM intake. Only question is if I’m putting it on my unknown 302, or picking up a GT40P motor for a winter project. :)
1.12 1964 Galaxie 390. KA and probably BA. The primary (KA) was also used on 289 4bbls. (earlier ones)
I believe the C4AF-DJ carb is also part of that group of weird ones that I mentioned in post #9.
 
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Thanks for the intel. Yeah, I noticed that the ‘DJ’ doesn’t show up on some lists of carburetors. We’ll see how she runs once I’m done!

1.12 1964 Galaxie 390. KA and probably BA. The primary (KA) was also used on 289 4bbls. (earlier ones)
I believe the C4AF-DJ carb is also part of that group of weird ones that I mentioned in post #9.
 

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Interesting. I recently saw a post from a guy who was considering buying a 1.12 from a 64 Comet. I might inquire more about it.
The Comet "K" code motor was NOT a HiPo. It was for all intents and purposes, a "D" code motor with a chrome dress-up kit. The carb was a 1.12... C4GF-E. Yes, there are some "early" HiPo exhaust manifolds for Fairlane's, C3OE-C, that had the "stove" for the hot air choke. Mustangs never had this feature.
 

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The Comet "K" code motor was NOT a HiPo. It was for all intents and purposes, a "D" code motor with a chrome dress-up kit. The carb was a 1.12... C4GF-E. Yes, there are some "early" HiPo exhaust manifolds for Fairlane's, C3OE-C, that had the "stove" for the hot air choke. Mustangs never had this feature.
Thanks Bart, Any idea why Ford used a 1.12 carb on it?
 

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Nope but, hey, I used a 1.19 on a 221.....
Lol, anything is possible..

I’m just trying to decide if the 1.12 might work better than my 1.08 for my 289 when I warm it up with GT40 heads and a Cam.
 

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Lol, anything is possible..

I’m just trying to decide if the 1.12 might work better than my 1.08 for my 289 when I warm it up with GT40 heads and a Cam.
My heads were ported some and with my cam the 1.12 was good, but somebody wanted it more than I did, and it justified my refreshing the 1.08 to go on my 289.
 
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