carb base measurements

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May 26, 2023 | 10:35 AM

artscott61

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From: southwest missouri

carb base measurements

I just purchased a 2 x 2 offenhauser manifold for a 51 flathead. The carbs i have will not fit on the manifold. The offenhauser measures 3" center bolt to center. Does anyone know what carb I might have to use ? The carbs I have now are the holley ford.

May 26, 2023 | 01:52 PM

ALBUQ F-1

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From: NM

I'm not clear what you mean by "center bolt to center"? 3 bolts? Does the Offy manifold have a p/n cast into it? Any chance it is for an earlier 59-series flathead?

May 26, 2023 | 02:14 PM

bmoran4

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From: Western NY

For a 51 flathead, it should be an Offenhauser 1075/1076 that accepts the standard 3 stud carburators {Holley 94 variants, Stromberg 97, Holley 2100 etc)

May 26, 2023 | 04:26 PM

artscott61

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From: southwest missouri

It is a 1075 looks to be cast in 3/12/97 which doesn't mean much. Ross the two rear bolt holes is what I am talking about. What I meant is the center of the hole to the center of the other rear hole.

May 26, 2023 | 04:41 PM

bmoran4

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From: Western NY

I think the actual center to center is 3 3/32"

May 26, 2023 | 05:06 PM

artscott61

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From: southwest missouri

Well now I have made an *** of myself. I put in the new studs that I bought and set the carb on and low and behold it fit. I want to thank all of you for responding. So much for just eye balling things. Thanks again guys and hope you have a good Memorial Day remembering our Vets that have passed before us. I have been around flatheads most of my life but not to the extent that I am going to get into them now.