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took the car out for the first drive of the year and I am still having the issues where if you push the gas to fast the car bogs down like it’s being flooded. My thought is it’s ether getting to much gas or it’s not getting enough and that I either need to clean/tune the carb and possibly jets. Has anybody else ran into the issue and might have more of an idea what it could be?
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What's the outside temperature? If it's still cool (< 50) it could simply be the air is so dense that you're experiencing a temporary lean condition...a bump up on the accelerator pump shot may be a temporary fix.

Is this something that "came on" versus "been that way" since you installed the carburetor or did some other work? Have you studied the AVS/AFB enrichment circuit and the function of the metering rods and jets? Perhaps the secondaries are opening too fast? The AVS/AFB tuning guide can help....

https://edelbrock-instructions-v1.s3.amazonaws.com/edelbrock/carb-tuning-guide.pdf
 

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check the vacuum advance canister
 

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Discussion Starter #4
What's the outside temperature? If it's still cool (< 50) it could simply be the air is so dense that you're experiencing a temporary lean condition...a bump up on the accelerator pump shot may be a temporary fix.

Is this something that "came on" versus "been that way" since you installed the carburetor or did some other work? Have you studied the AVS/AFB enrichment circuit and the function of the metering rods and jets? Perhaps the secondaries are opening too fast? The AVS/AFB tuning guide can help....

https://edelbrock-instructions-v1.s3.amazonaws.com/edelbrock/carb-tuning-guide.pdf
been like this since I got it last year. Figured it was acting up since it sat so long outside uncovered before I got it. I’ll look into that tuning guide and try studying up a little
 

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sorta sounds to me like the accelerator pump is either not working, or not delivering enough gas. Look in the primary Venturi, without the engine running, and open the throttle rapidly, and see if you see a strong stream of gas in both sides.
 

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You check the vacuum advance canister to see if it holds a vacuum. It is good to check this once in a while anyway.

Something to think about...
Instrumentation provides data so we don't have to guess so much. With this in mind, consider adding an AFR (air to fuel ratio) gauge. To do this, you will need to add an O2 bung into your exhaust and install a gauge. With this, you will know if you're running lean or rich when you are diagnosing things. The one I have is the AEM 30-0300 X-Series gauge. It really helped me tune my carburetor. Look up the choice of gauges and search on YouTube for good videos about the AFR gauges.
 

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I had a similar symptom with a 66 C code car, but it was with a stock 2100 carb. I ended up rebuilding the carb and I think it was a blocked passage in one of the booster venturis. The car also had a vacuum leak between the carb riser and manifold which was easily remedied with a new gasket.
 

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Sounds like it needs fuel to me. I'm on the "check the accelerator pump" bus. Apparently Carter/Edelbrock accelerator pumps don't like our modern ethanol laced fuel, I've had to replace a couple. Happily they don't cost too much, aren't hard to replace, and are available at many local parts stores. I've found some hanging on the wall in the "performance" section of the local Oreilly's Auto Parts for example
 

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been like this since I got it last year. Figured it was acting up since it sat so long outside uncovered before I got it. I’ll look into that tuning guide and try studying up a little
If it sat for a long time, especially if it had E10 or E15 in the tank the chances are that your fuel is crap. You might find the need to drain and flush your ENTIRE fuel system, including the carb bowls, and refill with "fresh" fuel.
 

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If it falls flat on its face when you open the throttle I don't think that would be a bad vacuum advance. That would be a sluggish feeling that continued as you accelerated but would not feel like it momentarily ran out of fuel. If an engine is way too lean, like if an accelerator pump does not spray it will cough back through the carburetor. That's always a hint of a lean engine.
First thing is to look in the carb with the engine off and see if you see a good squirt of fuel when you open the throttle. Some carburetors allow you to adjust the accelerator pump to squirt longer or shorter times. Some let you adjust the nozzle size. If it wants to bog down when you quickly open the throttle you can try at the same time you open the throttle squirting some starting fluid in there and see if that helps. That will give you an idea if the engine wants more fuel.

There is a flat spot in a carburetor as it switches between the idle circuit and the main circuit. The idle circuits shuts off but It takes a second for the vacuum to start pulling fuel out of the main circuit. To make up for that loss of fuel the accelerator adds some extra fuel.

You can have a power valve opening too soon. You can have secondary's opening too soon. There is a lot of fiddling around getting an aftermarket carb dialed in. Sometimes they work great out of the box and other times you have to change some parts to get them to work with your engine. That where of air fuel ratio gauge helps you dial them in.

Fixing a hesitation in an Edelbrock carb.

Hesitation or Bog?

Excellent Holley video on adjusting accelerator pumps

 

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Discussion Starter #14
If it falls flat on its face when you open the throttle I don't think that would be a bad vacuum advance. That would be a sluggish feeling that continued as you accelerated but would not feel like it momentarily ran out of fuel. If an engine is way too lean, like if an accelerator pump does not spray it will cough back through the carburetor. That's always a hint of a lean engine.
First thing is to look in the carb with the engine off and see if you see a good squirt of fuel when you open the throttle. Some carburetors allow you to adjust the accelerator pump to squirt longer or shorter times. Some let you adjust the nozzle size. If it wants to bog down when you quickly open the throttle you can try at the same time you open the throttle squirting some starting fluid in there and see if that helps. That will give you an idea if the engine wants more fuel.

There is a flat spot in a carburetor as it switches between the idle circuit and the main circuit. The idle circuits shuts off but It takes a second for the vacuum to start pulling fuel out of the main circuit. To make up for that loss of fuel the accelerator adds some extra fuel.

You can have a power valve opening too soon. You can have secondary's opening too soon. There is a lot of fiddling around getting an aftermarket carb dialed in. Sometimes they work great out of the box and other times you have to change some parts to get them to work with your engine. That where of air fuel ratio gauge helps you dial them in.

Fixing a hesitation in an Edelbrock carb.

Hesitation or Bog?

Excellent Holley video on adjusting accelerator pumps

thank you!!! This is very helpful info
 

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Did you let the engine warm up to operating temp before you tried this? I have to do that but then my hot rod carburator doesn't have a choke.
 

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Discussion Starter #16
If it sat for a long time, especially if it had E10 or E15 in the tank the chances are that your fuel is crap. You might find the need to drain and flush your ENTIRE fuel system, including the carb bowls, and refill with "fresh" fuel.
so
You check the vacuum advance canister to see if it holds a vacuum. It is good to check this once in a while anyway.

Something to think about...
Instrumentation provides data so we don't have to guess so much. With this in mind, consider adding an AFR (air to fuel ratio) gauge. To do this, you will need to add an O2 bung into your exhaust and install a gauge. With this, you will know if you're running lean or rich when you are diagnosing things. The one I have is the AEM 30-0300 X-Series gauge. It really helped me tune my carburetor. Look up the choice of gauges and search on YouTube for good videos about the AFR gauges.
Sounds like a great idea. Do you have pictures of your setup?
 

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Sounds like it needs fuel to me. I'm on the "check the accelerator pump" bus. Apparently Carter/Edelbrock accelerator pumps don't like our modern ethanol laced fuel, I've had to replace a couple. Happily they don't cost too much, aren't hard to replace, and are available at many local parts stores. I've found some hanging on the wall in the "performance" section of the local Oreilly's Auto Parts for example
thank you for the info. Helps to narrow things down
 
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