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Discussion Starter #1
I have a 1967 mustang fastback 289 bored out to a 302 by the owner before me, the car starts right up no problem and idles great, the only problem Is when im at a complete stop and step on the gas, the whole car boggs down and sputters, then catches itself and finally kicks in, im going to the store today to pick up a new ignition coil, I've had the car for about 10 years and never changed the coil, any other suggestions will be greatly appreciated.

Im also not the most knowledgeable person when it comes to cars, but any suggestion will help, and youtube can teach me the rest.

Thank You!
 

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Spammer Hammer
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I think we just had this discussion a month or so ago. Maybe not with you. What is the health state of your carb? What size is it? What size jets are installed.? Are the floats adjusted properly? And so on and so on. What is the ignition timing set too?
 

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Discussion Starter #3
Honestly everything about the engine of this car is old, it runs great, Im pretty sure I have a 4 barrel carb, not positive on that, ill check when im off work, No idea about the jet size, the float position or ignition timing.... I haven't had my car with me for 7 years, its been sitting in my parents garage, just recently moved back to my hometown so I was finally able to drive my baby again.

the engine is strong and starts right up every time, the only problem I have ever had with this car is the bogging down when I step on it in first gear from a stop, if I'm in second it wont hesitate at all and you can really feel the power.

Like I said, I'm not the most knowledgeable about working on cars, but I'm trying to get there.
Thank you for the reply!
 

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My car used to do that when it wasn’t warmed up all the way. Is your choke fully open? All around this sounds like a simple carb adjustment issue, maybe some timing as well. Pretty simple for someone with experience but it’s a bit harder to narrow it down via forum. You might wanna post in one of the regional forums here on VMF (whatever is closest to you) and see if an experienced member will come over and help you tune your motor in exchange for free beer and pizza.
 

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Spammer Hammer
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Discussion Starter #6
My car used to do that when it wasn’t warmed up all the way. Is your choke fully open? All around this sounds like a simple carb adjustment issue, maybe some timing as well. Pretty simple for someone with experience but it’s a bit harder to narrow it down via forum. You might wanna post in one of the regional forums here on VMF (whatever is closest to you) and see if an experienced member will come over and help you tune your motor in exchange for free beer and pizza.
Yea I make sure to warm it up before driving, choke is open, I hope it is just carb adjustment, ill look into tuning it or finding someone to come out, Thank You!
 

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Discussion Starter #7
I would suggest one of these and dive right in...

Good Call im pretty sure my pops has these laying around in his garage ill check it out, thanks again!

could my Coil have anything to do with the bogging down issue? I've read a couple places that this has been the problem, thoughts?
 

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Good Call im pretty sure my pops has these laying around in his garage ill check it out, thanks again!

could my Coil have anything to do with the bogging down issue? I've read a couple places that this has been the problem, thoughts?
Highly unlikely, but I never say never.
 

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65 Fastback 289 4 spd, 65 convertible 5.0L 5 spd. 3.73 8.8
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Good Call im pretty sure my pops has these laying around in his garage ill check it out, thanks again!

could my Coil have anything to do with the bogging down issue? I've read a couple places that this has been the problem, thoughts?
It won't be the coil, when they get warm they won't start, or they will die. It sounds like carb. With car off, air cleaner off, push on the accelerator pump to see if it pumps gas. Could be the float.
 

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Discussion Starter #10
So I replaced the coil and it made a HUUGE difference on acceleration, no more sputtering, it took all the choppiness away from accelerating, still a little bit of a bog when I gas it.
I have a 4 barrel carb right now and I think it might be too big for my engine, My car came with a 2 barrel on it but I got a 4 barrel holley for free from a friend so I've had that on for years, now that im troubleshooting this issue I think I'm gonna go back to the 2-barrel and see what happens. Thanks for the input guys!!
 

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Why go through all the extra work to swap intake manifolds (from 4 barrel to 2 barrel) when your carb probably just needs to be cleaned up? Also, additional info on what brand of carb it is would be helpful. They usually also have some identifying numbers on them that folks here can translate into english and also provide some general guidance on whether or not the carb is appropriately sized for your engine. Pictures are useful if you don't know what you're looking at (no insult intended....).

Harry Z
 

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A largely overlooked aspect of engine tuning is having the distributor advance curves adjusted. At one time was considered part of a normal tune-up, but now largely unknown.
 

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So I replaced the coil and it made a HUUGE difference on acceleration, no more sputtering, it took all the choppiness away from accelerating, still a little bit of a bog when I gas it.
I have a 4 barrel carb right now and I think it might be too big for my engine, My car came with a 2 barrel on it but I got a 4 barrel holley for free from a friend so I've had that on for years, now that im troubleshooting this issue I think I'm gonna go back to the 2-barrel and see what happens. Thanks for the input guys!!
Please include a picture of this 4V carb.
 

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Post the list number on the carb air horn. There's plenty of great references out there on how to properly tune your Holley. It's fairly straight forward, there's parts-a-plenty and they need it. Poorly adjusted they do all sorts of crazy. No need to get drastic when probably a rebuild and tune is all you need. Don't guess. They are very adjustable which means you can spend more time in the weeds than not.
 

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Discussion Starter #15
Post the list number on the carb air horn. There's plenty of great references out there on how to properly tune your Holley. It's fairly straight forward, there's parts-a-plenty and they need it. Poorly adjusted they do all sorts of crazy. No need to get drastic when probably a rebuild and tune is all you need. Don't guess. They are very adjustable which means you can spend more time in the weeds than not.
Awesome! thank you! ill try tuning it, clean it up, maybe get some new gaskets and see what happens.
 

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The job of the accelerator pump on a carburetor is to squirt in extra fuel to richen the mixture when you quickly press the accelerator pedal. This is needed to avoid having the engine bog down when you step on the gas. Verify that your accelerator pump is functioning properly. Do a little research into accelerator pumps and adjustments so you will know what you are looking for.
 

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Discussion Starter #17
(y) will do, gonna get a new accelerator pump for sure, try that out, if that doesnt work, I think Im going to buy a smaller 4 barrel carb rather than switching for a 2 barrel, hopefully with the carb and accelerator pump ill be runnin smooth, ill probably get a tune up at the end of all this as well.

Thank you all!
 

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You might wanna post in one of our regional forums and check to see it there’s someone experienced local to you who might help you tune it in exchange for some beer and pizza.
 
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