Stromberg carburetor size question...

[JV Puleo]

How does the Stromberg model/number system work? I've been trying to work this out but am getting conflicting information. My understanding thus far is that an "Hno2" would be a "Model H" number "2" with a throat opening of 1 3/8"... or did these measurements change between models so that the size measurement is different depending on which model it is?

Thanks,

[Guest Jim_Edwards]

I believe this link will answer whatever questions you may have.

THE CARBURETOR SHOP LLC / Decoding Stromberg carburetors

[JV Puleo]

I should have been more precise... I'm interested in pre 1920 cars and that chart says, at the top, that its only applicable to post-1934 carburetors... they may be the same though, I just don't know.

[Guest Jim_Edwards]

Unfortunately I think this describes trying to identify pre-1935 Stromberg carburetors to a "T."

"Stromberg carburetors produced prior to 1935 can easily be identified as to type, as it is cast onto the carburetor; however complete identification is impossible unless one has prior knowledge of the carburetor being identified; and can be quite difficult and time consuming for even someone with the original prints."

May I ask why you need to identify one beyond the basic vehicle application?

[carbking]

This link may help a bit more:

THE CARBURETOR SHOP / Stromberg updraft carburetors

All H no 2 carbs should have the same center to center mounting and bore size; but different internal venturi sizes were used, thus changing the air flow from model to model.

Jon.

[JV Puleo]

I'm interested in using one on a project brass car, a 1910 Mitchell "T" ... the size is important. I haven't been able to find out what carburetor came on it originally. In any case, they were frequently changed in period both by owners and with some makers offering 2 or 3 different options. (Hudson offered 3 in 1910) In my case, the engine will have new aluminum pistons, a slightly higher compression ratio and generally much better breathing characteristics. The original was probably undersized to begin with. Its a matter of finding something appropriate - I'm not terribly concerned with having exactly what the car came with but do not want to use something that is inappropriate for the period.

Carbking, thanks. That is what I was looking for. I must have missed it on your site. I realize the venturi's can be different... I may have to make those, but I need to start with something and getting one with a throat diameter that is too small from the start is not going to help. Thanks again.

Edited November 13, 2011 by JV Puleo (see edit history)

[carbking]

We show that Mitchell used a Holley Brothers 1 1/4 iinch carburetor on the 30 HP T series in 1910. This statement can be misleading! A 1 1/4 inch carburetor would be an S.A.E. size 2 carburetor with a "nominal" 1 1/4 inch size. Depending on the make and efficiency of the carburetor, a "nominal" 1 1/4 inch carburetor would have a throat (bore) size of 1 7/16 (efficient) to maybe 1 9/16 (something less than efficient). The 1 1/4 inch carburetor (S.A.E. size 2) would normally have a mounting bolt spacing of 2 11/16 center to center. Of course, there are exceptions to this normality.

The Stromberg H-2 was used on several engines larger than the 284 CID Mitchell; and should be plenty of carburetor (at least size-wise) for the Mitchell.

The model H was the last of the glass bowl Strombergs. Unless the glass bowl is important to you, I would suggest the later M series (brass) or the still later O series (still brass) is technologically superior to the H.

Jon.

[JV Puleo]

I confess I like the archaic look of the B and H models but in the long run, that doesn't make the engine run any better. I'm trying to stick to components that were available during the car's working life (when they are visible) - which I'm guessing was pretty much over by 1915.

The intake manifold layout is positively tortured... with the carburetor on the right-hand side of the engine and the actual manifold on the left... connected by a long tube that runs diagonally between the blocks. Does this effect efficiency? I would think it must, but in what way?

The H model may be too big, since it has to fit between the blocks/crankcase and the oiler that is also on the right...

I'm just trying to think ahead. It will likely be a year or more before its even ready to run and even then the chassis won't be ready for it. But, with that much time I think its a good idea to settle on what will probably work best and patiently go about trying to find it.

Edited November 14, 2011 by JV Puleo (see edit history)

[Stutz in the UK]

Bit of a long shot, but does anyone have a tuning booklet for the H Series Carburattors they could scan and email me please?

Thanks

I confess I like the archaic look of the B and H models but in the long run, that doesn't make the engine run any better. I'm trying to stick to components that were available during the car's working life (when they are visible) - which I'm guessing was pretty much over by 1915.

The intake manifold layout is positively tortured... with the carburetor on the right-hand side of the engine and the actual manifold on the left... connected by a long tube that runs diagonally between the blocks. Does this effect efficiency? I would think it must, but in what way?

The H model may be too big, since it has to fit between the blocks/crankcase and the oiler that is also on the right...

I'm just trying to think ahead. It will likely be a year or more before its even ready to run and even then the chassis won't be ready for it. But, with that much time I think its a good idea to settle on what will probably work best and patiently go about trying to find it.