Question about using Brumfield head

[mcgarrett]

Brent,
I forgot about the choke rod alignment issue with the B carburetor. I had a similar alignment issue with the choke rod on my Model T Speedster where the rod angle to the carb was different, but I used a flexible brake hone shaft and modified it to fit the choke rod and seemed to work perfectly. I might give that a try here and see if I have the same success.

Regarding stud hole threads, 3 of them need to be drilled and Heli-Coils installed. I want to be sure I drill and tap the holes spot-on. Do you recommend having a machine shop do this or take it on myself? I'm fairly competent using a tap, but I don't want to screw this up. I thought about fabricating a fixture to make sure I drill the initial hole perfectly vertical and square to the block. Thanks for your recommendations.

[Hitman]

Originally Posted by BRENT in 10-uh-C

Well, the 'B' manifold does not need any modification when used with a 'B' carburetor on a 1932-34 4 cylinder engine however the issue when using the Model-B intake on a Model-A is the carburetor is aligned differently which prohibits the Model-A Choke Rod from connecting to the GAV. Additionally, the Model-A style of fuel line enters the Model-B carburetor in a different location requiring either a new line to be fabricated or an original line being modified. Therefore, to use a Model-B intake requires the carburetor mounting flange to be modified by either cutting the flange and rotating, -or elongating the carburetor mounting holes (risky).

FWIW, since the external shape of the Model-B intake manifold is different too (-making it noticeably obvious), I prefer to modify the stock Model-A manifold by boring the inside about 5% larger than a Model-B, -which is about 30% larger than a stock Model-A intake manifold.

I run a B carb and intake on one of mine without any modification to the carb or manifold. I just turn the carb mounting bolts down a bit to correct the alignment issue. This avoids having to modify the manifold and risk damaging the bolt flange.

Making a new fuel line isn't difficult.

[mcgarrett]

Originally Posted by Hitman

I run a B carb and intake on one of mine without any modification to the carb or manifold. I just turn the carb mounting bolts down a bit to correct the alignmuent issue. This avoids having to modify the manifold and risk damaging the bolt flange.

Making a new fuel line isn't difficult.

Hitman,
Can you please clarify what you mean by "turn down the mounting bolts down a bit" ?

[Keith True]

You can also use a late 31 sidebowl on the B carb,it will put the inlet in a position where you just need to pull on the A fuel line a little to hook it up.Looks like it belongs there too.Wasn't somebody making an offset machined set of bolts to use the B carb on the A?

[mcgarrett]

Keith,
Good idea using the side-bowl connection on the B carb!

[BRENT in 10-uh-C]

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Originally Posted by Keith True

You can also use a late 31 sidebowl on the B carb,it will put the inlet in a position where you just need to pull on the A fuel line a little to hook it up.Looks like it belongs there too.Wasn't somebody making an offset machined set of bolts to use the B carb on the A?

Yeah, I think they were first introduced on a TV show called MacGuyver!!


In all seriousness, that might be acceptable protocol for some folks but that is not for me. I know, ...Geez, what could possibly happen if one or both of those modified bolts broke??

[Benson]

Originally Posted by Keith True

You can also use a late 31 sidebowl on the B carb,it will put the inlet in a position where you just need to pull on the A fuel line a little to hook it up.Looks like it belongs there too.Wasn't somebody making an offset machined set of bolts to use the B carb on the A?

Yes several vendors that I have seen are carrying such bolts.

In 1963 we also turned down bolts to solve the problem when fitting B carbureators.

In high school one guy (I will not name names but he also used an electric drill motor clamped to a bench and a file to turn them down)

ALSO he chucked the bolts up in a drill press and used a file to turn them down.

[Y-Blockhead]

Originally Posted by Keith True

Wasn't somebody making an offset machined set of bolts to use the B carb on the A?

Renner's Corner

[Hitman]

Originally Posted by mcgarrett

Hitman,
Can you please clarify what you mean by "turn down the mounting bolts down a bit" ?

Y-block posted a picture of what I did. I wasn't aware that someone was making these for sale.

Basically, as you see you turn down the upper half of the bolt shank to allow the carb to rotate in the manifold flange. You do both so you don't pivot off one, and turn both bolts a small amount as you can see. Turning both bolts also keeps the port aligned.

The strength isn't really compromised much, and the carb doesn't take much "torque" to keep it in place.

[mcgarrett]

Hitman,
Understood - thank you for the clarification.

[Keith True]

I just took a little off the sides of the 4 holes with a chainsaw file.When you do all 4 like that the amount taken off is miniscule.I do remember it didn't take very long,it was back in the late 70's.I didn't come up with the idea of using the late 31 sidebowl,I bought a carb all set up that way.Since then I've seen a couple done that way.I just came across a carb I have set up with the sidebowl,but it won't do me any good to take a picture,I can't post them here anymore.

[katy]

Originally Posted by mcgarrett

Regarding stud hole threads, 3 of them need to be drilled and Heli-Coils installed. I want to be sure I drill and tap the holes spot-on. Do you recommend having a machine shop do this or take it on myself? I'm fairly competent using a tap, but I don't want to screw this up. I thought about fabricating a fixture to make sure I drill the initial hole perfectly vertical and square to the block. Thanks for your recommendations.

If you're talking about the head studs, use a cylinder head for a guide, clamp it down with 2, 3 or more studs, bolts or whatever.

[mcgarrett]

Katy,
That's probably what I'll end up doing. Thanks.

[Benson]

Originally Posted by Keith True

I just took a little off the sides of the 4 holes with a chainsaw file.When you do all 4 like that the amount taken off is miniscule.I do remember it didn't take very long,it was back in the late 70's.I didn't come up with the idea of using the late 31 sidebowl,I bought a carb all set up that way.Since then I've seen a couple done that way.I just came across a carb I have set up with the sidebowl,but it won't do me any good to take a picture,I can't post them here anymore.

Keith,

Is this a photo of B carb setup that you are referring to?

I ran a few this way in the past.

I did not come up with the idea either.

I think Bill Kenz RIP or Paul Garrigan RIP showed it to me in the 60's.

[Keith True]

That's the setup I have around.Also,on the one I ran in the late 70's somebody had drilled the threads out of the ears,so it probably had a little more play to work with.

[katy]

mcg, be careful that you don't overdrill down into the water jacket, a "depth stop" on the drill bit might be in order.

[Marshall V. Daut]

I took a regular fuel line from the sediment bowl to the carb and filled it with sand, plugging the ends with wadding. Then I was able to bend the line at the lower end into a "U" facing towards the rear of the car to match the location of the "B" carb's fuel line inlet without kinking the tubing. The sand keeps the line from pinching and kinking. Go slow and test fit to get the approximate angle needed. The angle of the tubing from the sediment bowl to the carb will be increased from its usual near vertical orientation, but so what? By installing a "B" carb, you're altering an "originality" look anyway. Then drain the sand and blow out the line BOTH WAYS with compressed air to get rid of any sand particle. Just be sure to get all the sand out. Once you are sure the line is squeaky clean inside, screw in the ferrule at the sediment bowl and complete the final bending to fit into the carb's fuel inlet. It will look like the line was made that way!
Marshall