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Parts For Sale WTB Autolite 4300 D carburetor

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Dirconmach1

Well-known member
Joined
Nov 14, 2019
Messages
76
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8
Location
Fort Valley,Virginia
My Car
1971 Mach 1 351 Cleveland, 4 barrel, ram air, 4 speed, factory a/c, 77 k original miles in bright red with black.

Drive it like you stole it!
Looking for a rebuilt Autolite 4300 D carburetor or a good used one that can be rebuilt. PM me Thanks
 
From reading your car specs, you would need a 4300, not a 4300D which is the spread bore. The 71 4V is not a spread bore unless your intake has been changed to a later one.
Unless you need to keep it totally original, I'd suggest a Holley 670 or Quick Fuel of similar size.
Just asking the question.
 
Ru u worried about production date also auto or spd
Dated 7/71, 351 Cleveland 4 barrel, 4 speed car. Not having the correct date isn’t a deal breaker. Thanks. Let me know.
 
From reading your car specs, you would need a 4300, not a 4300D which is the spread bore. The 71 4V is not a spread bore unless your intake has been changed to a later one.
Unless you need to keep it totally original, I'd suggest a Holley 670 or Quick Fuel of similar size.
Just asking the question.
It has a Holley on it now. Where the 4300D used on open chambered heads? I know mine are closed chambers heads. The car came with Holley on it when I purchased it. Always had a hard time starting. Looking to put back the correct carb. From what I can see, it’s mostly original except for the paint? Thanks
 
It has a Holley on it now. Where the 4300D used on open chambered heads? I know mine are closed chambers heads. The car came with Holley on it when I purchased it. Always had a hard time starting. Looking to put back the correct carb. From what I can see, it’s mostly original except for the paint? Thanks
The 4300D was a spread bore carb, i.e. the secondary's are larger than the primary's and were used on the 72 Q code motors and a slightly different version on the 71 Boss and 72 R code motors. 72 Q code head are different to the 71 M code and are open chamber.
Personally I have no experience with a 4300, mine is sitting on the shelf and that's where it's going to stay. I only keep it as it was ( I believe) original to my car, unfortunately with no tag, so I can't be sure.
I am pretty sure anyone here will tell you the same thing. Unless it's a concour car, forget it. If your Holley needs a rebuild as it sounds like it does, then I'd look at that first. Kits are easy to get and lots of videos on YouTube I'm sure to help. Failing that, take it to someone who can rebuild it for you, like a local speed shop.
That's just my unqualified opinion.
 
The 4300D was a spread bore carb, i.e. the secondary's are larger than the primary's and were used on the 72 Q code motors and a slightly different version on the 71 Boss and 72 R code motors. 72 Q code head are different to the 71 M code and are open chamber.
Personally I have no experience with a 4300, mine is sitting on the shelf and that's where it's going to stay. I only keep it as it was ( I believe) original to my car, unfortunately with no tag, so I can't be sure.
I am pretty sure anyone here will tell you the same thing. Unless it's a concour car, forget it. If your Holley needs a rebuild as it sounds like it does, then I'd look at that first. Kits are easy to get and lots of videos on YouTube I'm sure to help. Failing that, take it to someone who can rebuild it for you, like a local speed shop.
That's just my unqualified opinion.
Thanks for the update. I’m still weighing my option. I just want it to run better.
 
I'll chime in with what I learned about Autolite 4300 carbs. They were designed to help meet emission standards and therefore were calibrated very lean.
Owners would take back 4300 equipped cars to dealers complaining of surging and poor drive ability. I actually used one on my 289 bracket Mustang but I didn't know what it was at the time. I bought it because it was a four barrel carburetor that another racer was using on his Falcon. I was still in my early learning curve at the time. It was a 4300D because I remember the huge secondary bores and having to tweak the opening rate on them. It was considered a mechanic's nightmare because of all the parts it had. When the accelerator pump started to fail I sold it cheap to someone and got a Holley.
I would ditch the 4300 and suggest calling Dan at DaVinci Carburetor. He can build you a Holley carb based on your car's engine set-up.
It won't be cheap but it will work flawlessly as delivered. I know this from personal experience.
 
I'll chime in with what I learned about Autolite 4300 carbs. They were designed to help meet emission standards and therefore were calibrated very lean.
Owners would take back 4300 equipped cars to dealers complaining of surging and poor drive ability. I actually used one on my 289 bracket Mustang but I didn't know what it was at the time. I bought it because it was a four barrel carburetor that another racer was using on his Falcon. I was still in my early learning curve at the time. It was a 4300D because I remember the huge secondary bores and having to tweak the opening rate on them. It was considered a mechanic's nightmare because of all the parts it had. When the accelerator pump started to fail I sold it cheap to someone and got a Holley.
I would ditch the 4300 and suggest calling Dan at DaVinci Carburetor. He can build you a Holley carb based on your car's engine set-up.
It won't be cheap but it will work flawlessly as delivered. I know this from personal experience.
I guess I’m going to have to go with rebuilding the Holley that’s on it. Thanks for your input. I really just want it to start and drive better. Thanks what you said is kind of what everyone else says. On the bright side I’ll probably save some money. Thanks
 
Had a 4300 on my 1972 Cobra Jet, rebuilt it so many times, I would joke, I could do it in the dark. Finally put a fuel pressure regulator on it and it ran beautiful after that. You will love the gel filled high idle pull off, I was buying parts from Ford back then. Only ever got 6 mpg, but it would smoke both back tires at 60 mph.
 
Had a 4300 on my 1972 Cobra Jet, rebuilt it so many times, I would joke, I could do it in the dark. Finally put a fuel pressure regulator on it and it ran beautiful after that. You will love the gel filled high idle pull off, I was buying parts from Ford back then. Only ever got 6 mpg, but it would smoke both back tires at 60 mph.
Do you remember what the fuel pressure was before and after you installed the regulator? Chuck
 
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