BBC jets

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wheelsport

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Does anyone know the correct jet size for a BBC carter on a 273 with an automatic? The carb I have now is from a junk yard. I have no idea what car it came from. I rebuilt it and it runs fine except it runs rich and I haven't been able to lean out.
 
What year and model are you working with? Do you have a carb number?
 
Are the jets on a BBD on the idle circuit?
 
"65 Barracuda. The '65's BBD numbers range between 3843s-3850s. My carb number is 4952s which would make it more likely from a '71 318.
 
"65 Barracuda. The '65's BBD numbers range between 3843s-3850s. My carb number is 4952s which would make it more likely from a '71 318.
I have the numbers for 1966, which should be very similar. The manual and automatic trans non-C.A.P. have (as standard) a 120-294S main jet with a 75-1734 two step metering rod measuring .026 and .021 on the manual trans, and 75-1736, .027 and .021 on the automatic. One step leaner uses 120-297S jets, and two steps leaner uses 120-298S jets, using the same metering rods. The C.A.P. versions are 120-310S as standard ( both manual and automatic), with the 75-1641, .028 and .025 rods in the manual applications, and 75-1727 , .029 and .025 in the automatic. Next step leaner is 120-294S, and two steps leaner is 120-297S with the same rods. respectively. If I can find my factory Carter book, I'll verify it the same for the '65 model year. I'm not seeing a 4952 listed for any cars or light trucks. Maybe something heavy duty or industrial? Post a photo maybe?
 
I took a closer look at the carb tab-the number is 4947 which doesn't show on the chart for a '71. There are no numbers on the jets but a .041 drill fits which is the smallest jet for this carb. The metering rod measures .013 /.005, which doesn't match any of your rod sizes.

Another thing also, I noticed that there is only a tiny amount of fuel in the bowl. I filled the bowl with thinner to see if any plugs might be leaking but can't see anything.
 
I'm not showing that one either. The only reference I have to that number says it's obsolete and not listed in the book I have.
 
It really doesn't matter if that carb is obsolete. The main difference in each model is the size of the jets. My carb is seeping fuel under the accelerator pump. Carbs Unlimited carries BBD jets but no metering rods. Is there any place to obtain metering rods?
 
It really doesn't matter if that carb is obsolete. The main difference in each model is the size of the jets. My carb is seeping fuel under the accelerator pump. Carbs Unlimited carries BBD jets but no metering rods. Is there any place to obtain metering rods?
I would just try getting the proper carb for your application first. If you want to play with the one you have, try contacting a carburetor shop (if there are of those around anymore). They're bound to have some, or are least a core to get some.
 
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