Difference of Model B or C carb.
- Thread starter josh1331
- Start date
MAG
Well-known member
Check out Vince's site. You will find a wealth of info. about the B carb.
http://www.deucegarage.com/
I run B's on my 3 Model A's and am very pleased with their performance. Coupled with a HC head and B cam makes a very nice running combination.
http://www.deucegarage.com/
I run B's on my 3 Model A's and am very pleased with their performance. Coupled with a HC head and B cam makes a very nice running combination.
Logan
Well-known member
just be sure if you decide to get a b carb, you bore out your intake manifold to b specs or else your not going to get the right amount of air flow that the b carb would need. So you wont be reaching all the potential of the carb. you will probably feel a difference with stock bore, but not as much with a B size bore.
Jerry in Shasta
Senior Member
The "B" carb has a .100 larger throat. So you need a "B" intake manifold, which I recommend, or bore the throat of an "A" intake manifold. The "B" intakes runners are also about .100 larger than an "A"
Second thing, you what to find a later square float bowl "B" carb. They have a better idle set-up and have later design improvements.
If you use a "B" manifold, you will find that the choke rod does not line up the same as the "A"s. You will need to get kit from one of the vendors to help realign it or you can do some filing and fiddling around and do it your self.
I have "B" carb and manifolds on both my cars and they make a noticeable difference!
Would I change back? Not with out a big fight, or a whole lot of money up front!
Just my W.A.G. at the problem
Jerry
Second thing, you what to find a later square float bowl "B" carb. They have a better idle set-up and have later design improvements.
If you use a "B" manifold, you will find that the choke rod does not line up the same as the "A"s. You will need to get kit from one of the vendors to help realign it or you can do some filing and fiddling around and do it your self.
I have "B" carb and manifolds on both my cars and they make a noticeable difference!
Would I change back? Not with out a big fight, or a whole lot of money up front!
Just my W.A.G. at the problem
Jerry
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Purdy Swoft
Well-known member
I have never heard them refered to as B or C. There is at least two versions that were used on the B or model 46 four cylinder engines, they are usually refered to as B1 or B2. The 32 B carbs had a barrel float. The B 2 had a rectangular float and a better idle curcuit. The B2 is the prefered carb . One has raised letters on the bowl, I should remember which but it is Too hot here to go outside and look. There was a version with a smaller venturi that was used as the first replacement on model A's after the model A zenith was discontinued.
Dave in MN
Well-known member
I agree with Logan. The "B" carb works better with larger intake manifold passages.
There are lots of methods to enlarge manifolds. I been enlarging "A" manifolds to "B" sizes for some time now using a simple setup. I have some photos of the set-up and "Do it yourself" tips of the process on my website if you are interested. There are a number of photos...so it takes a bit of time to load.
www.durableperformance.net
Look for the link on the Services page near the bottom under "Other Model A services:"
Good Day!
Dave in MN
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Purdy Swoft
Well-known member
I set up the model A intake manifold in a vise and ream the runner out to model B size witn adjustable reamers. It is a slow process but I have reamed several for myself and others.
I bought a set of Harbor freight adjustable reamers and they have also come in handy fitting repro model A parts.
