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I know it has been asked a ton, and I did a search, but most of the threads I found were older and not quite what I was looking for.

Car has a 289 with mild cam, intake and headers. Currently has an older Edelbrock/Weber 8867 carb, manual choke, no idea on cfm, etc... it's been adjusted a ton and I'm having issues getting it just right. Car runs ok, but is definitely running rich.

What would you recommend to replace?
 

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There are a lot of people who like the Edelbrock carbs, and maybe a guru here could help you get it 'right'. I never mastered the old AFB's, and Edelbrocks seem to be as much of a mystery to me.

My favorite new street carb is the Summit M-series. Very similar to the old 4100s, but with some nice features that make them easier to tune - like windows to actually see the fuel levels without taking the top off, and externally adjustable floats. Same old annular boosters, which give fantastic atomization. Great for performance and for economy. They also happen to be relatively inexpensive!

They come in sizes from 500 cfm to I think 750. For a mild 289, the 500 is perfect.
 

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A common problem with the Edelbrock carbs is too much fuel pressure. Do you have a pressure gage and know you have under 5.5 PSI fuel pressure? Frequently Ford pumps put out around 6 to 7 psi which is too much for the Edelbrock. If you are getting the tear gas smell at idle, this might be your issue.
 

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A Edelbrock carb should be a 140X number. Stamped on the carburetor mounting base tab.
What adjustments have you tried already? Just the idle mixture screws on the front?
These carbs are pretty easy. Most of the tuning can be done without opening up the carb. Just change metering rods and step up springs.

A little modern technology helps a lot for tuning carburetors. Installing a wide band air-fuel ratio (AFR) gauge will help. But they are a bit pricey.

The old fashioned way still works though.
 

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I ran a Street Demon 625 for like a year and a half and always had idle issues. Here in Texas I would get about 17 inches of vacuum. I switched to a Holley 600 and now have like 20 inches of vacuum and my car idles great. The Street Demon was awesome when I was driving though, excellent throttle response, power, and gas mileage. Although I feel like the Holley 600 has more low end power. I am running 64 jets in the primaries and that seems to be just about right.
 

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I've ran edelbrock, ford, holley, and qft. Edelbrock is easy to tune, and a great all around driving carb; 1406 is a good size for your app. Ford 4100 1.08 is a great carb, also good drivability. I took the dive into holley some time back and can say if you read and understand how to set them up, they are hands down better then 4100 and edel. QFT takes holley to the next level for performance tuning, with more features and tunibility. So, the question is how much do you want to work? I enjoy tuning a carb, but it takes time, and some reading. If you want a bolt on, go with edel 1406, auto choke and you should be set. If you want to learn, start with a holley 4150, center hung bowls, 600 cfm, vacuum sec's, and learn how to tune it. You'll be very happy.
 

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Ran a Holley for a cpl years, too finicky. Ran an Edelbrock 1406 for 21+ years, very easy to tune but always had a stumble coming out of hard corners and issues with hot percolation. I attribute this to the float locations and crappy fuel with the Eddie heat characteristics. Switched to a 66 Autolite 4100 and LOVE it. Not to mention it is a "period-correct" dealer-available accessory for my car. Looking forward to having the time to play with jets even though I really don't have to. If the Summit carb is at least as good as the Autolite, I would buy one if the correct Autolite was too expensive.
 

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My experience:

My 302 J-code (stock, 230HP @flywheel) mustang came with a 670 CFM Holley Street Avenger carb. It always ran rich and bogged (slightly) on acceleration. It was either too much carb (that is, too much cfm) and/or I didn't know how to tune it correctly.
I replaced it with a 1406 Edelbrock (600 CFM). Much better. Tuning is very straight forward (just read the book). But it was just "on the edge of tune-ability" for a stock 302. So I replaced it with an Edelbrock 1403 (500 CFM version... I actually just replaced the venturi boosters which is the same thing). Much more in the sweet spot of a stock 302 circa 1968. Much easier to tune.

What I would recommend is the Edelbrock AVS2 1903 which is the same as the 1403 except it has (i) a tune-able secondary and (ii) has annular venturi boosters on the primary. From reviews (from Summit racing, not experience) this seems to improve the fuel atomization and, thus, the throttle response from a dead stop over the 1403.

Two caveats on the Edelbrock carb (also mentioned above in the thread):
(1) Eddys don't like more than 5.5psi - 6psi on the fuel input. Measure what output pressure your fuel pump is creating. If > 6psi put a fuel pressure regulator after the pump and before the carb.
(2) The fuel in an Eddy's bowls (Holley's?) tend to boil when heat soaked, so a phenolic (heat insulator) spacer is a good idea.
 
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