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Discussion Starter #1
Im have a 66 mustang with the 200 in it. I just put the engine in and its running pretty good. There is the occasional spark from the carb though.
I am running the autolite 110 carb right now, but I have a remanufactured holley1940 and a remanufactured carter yf.
Is there a significant difference between the autolite, holley and carter? What are the pros and cons of each?
 

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A spark from the carb means it's back firing, and isn't usually a carb problem! Be careful you aren't posting pictures of a burned car soon! Get your timing right and that 1100 will be great for a stock-to-mild 200.
 
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Discussion Starter #3
A spark from the carb means it's back firing, and isn't usually a carb problem! Be careful you aren't posting pictures of a burned car soon! Get your timing right and that 1100 will be great for a stock-to-mild 200.
Thanks! Do you have any advice for troubleshooting backfiring?
 

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Inspect your distributor cap and rotor for corrosion, wear, or carbon tracing. Inspect spark plug wires for leaks (good to see in the dark). Check static (engine off) ignition timing, then set dynamic (running timing) until idle rpm and idle mixture (carb rich and lean) per specs. Make sure carb float is set correctly. Enjoy.
 

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It would help to know when the problem occurs. Is the engine cold, does it do it when you step on the throltle, does it do it just cruising with a the pedal held in one place. Was that a used carburetor you installed that should have been rebuilt first?

A backfire through the carburetor is usually a sign of a lean condition. Years ago I was taking an ASE or smog license test and there was a question on there, What causes a backfire through the carburetor? I had never thought about it so I tried reason in out and I made an uneducated guess . Went home, looked it up and I guessed wrong. I missed two questions and that was one of them. I' still have not forgiven myself for answering that question wrong

A lot of times its caused from a accelerator pump not working or not adjusted to squirt enough fuel.

It also happens if you install a distributor wrong and the plug fires while the intake valve is still open but that would be constant and not an occasional problem. A burned intake valve would also do the same thing but it would also be constant. The ignition system can also cause it. If the engine is not missing then its probably fuel related.

Causes

 

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Discussion Starter #6
It would help to know when the problem occurs. Is the engine cold, does it do it when you step on the throltle, does it do it just cruising with a the pedal held in one place. Was that a used carburetor you installed that should have been rebuilt first?

A backfire through the carburetor is usually a sign of a lean condition. Years ago I was taking an ASE or smog license test and there was a question on there, What causes a backfire through the carburetor? I had never thought about it so I tried reason in out and I made an uneducated guess . Went home, looked it up and I guessed wrong. I missed two questions and that was one of them. I' still have not forgiven myself for answering that question wrong

A lot of times its caused from a accelerator pump not working or not adjusted to squirt enough fuel.

It also happens if you install a distributor wrong and the plug fires while the intake valve is still open but that would be constant and not an occasional problem. A burned intake valve would also do the same thing but it would also be constant. The ignition system can also cause it. If the engine is not missing then its probably fuel related.

Causes

Thank you, it seems to be backfiting when I press down on the accelerator. I adjusted the air intake and it seemed to help. I might also look into rebuilding the carb as it is pretty old.
 
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