IDF dimensions

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friedman
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Re: IDF dimensions

Post by friedman » Sun Sep 08, 2019 8:04 am

It does sound odd, you would think a carb venturi would be bored consistent all the way through from top to bottom and adjustments made with the removable venturi. I don't have a 44 to make any measurements for you and my 40s are currently bolted to my X.
Carl in Virginia
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atruscott
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Re: IDF dimensions

Post by atruscott » Sun Sep 08, 2019 9:01 am

I’ll measure some carbs later. I’ve got Italian made Weber 40 and 44, along with Spanish made Weber 40 and 44, on the shelf.
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fiatfactory
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Re: IDF dimensions

Post by fiatfactory » Sat Oct 12, 2019 5:31 am

I just happen to be overhauling a set of IDF13/15's and also a set of 44IDF20/21's this weekend... and dug out my inside dividers and measured the ID of the throats just below the butterfly plates. (not measuring the slight chamfer at the very base of the carb throat)

40IDF 13/15 measure 40.15mm I.D.
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44IDF 20/21 measure 44.20mm I.D.
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maybe the EMPI /Chinese copies are smaller?

but it looks to me like 40mm in Italian is actually 40mm...

What do the auxiliary venturis look like on the set that you thought were 44's?
The aux venturi design of the 44's is much less restrictive than the 40's

SteveC
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