anyone know what used a weber DFO carburetor

Ebel440

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I bought a pair of Weber 40DFO carbs just to see if it would be possible to use them on a vw engine. The seller listed them as off a fiat but I have not found any evidence of fiat using them. I believe they are off an Opel of some type as that is the only car I have been able to find that use them. I'm familiar with most type of 2 barrel webers but don't remember ever seeing this type. It looks like it will fit a DCNF manifold but appears to be designed more like a DFAV/DFEV except it's got synchronous barrels. Has anyone used these carbs or have any ideas where to look for information about them? Is there a good weber book that has information about them? From my understanding of webers designation it's a down draft carb designed originally for Ferrari or Fiat but that's about all I know about them.
 
As you found, main ref is to Opel.

Early Ferrari V8's used 4 DCNF's. These have also been used on VW's with appropriate manifold. Wonderful carbs speaking from 10 years of pleasure hearing them behind me on a 308GT4

A good book on Weber carbs: https://books.google.com/books?id=OSLglUxPgiUC, you can use Search Inside to find your DFO

Your main challenge will be figuring out jetting, if they are interchangeable. Compare engine characteristics for the Opel and VW engines, if similar you stand a chance of it working.

Gerrit
 
i didn't run them but i did have a friend that did run them on his dual port VW.
there is a place in Hayward,Ca called the Buggy House-all they do is VW-
http://buggyhouse.com/

they may be able to help out.
good luck,
mike:))
 
I had an Opel gt and a 128 3p Fiat---I know that I still have the intake manifold for the Fiat in my other shop and may still have the carb for it--I will look at my manuals to see if either used the webers---Dave


*update---the Fiat 128 3p used a weber 32 DMTR two barrel
 
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Thanks ill see if they can help me out. I actually have a pair of 40 dcnfs for my vw already so ill see if the new ones fit. Did he have them in a full bodied car? I'm thinking they may be a little too wide for a bug. They should fit in a bus that I have though. The jets may be a problem though i saw something about jets may interchange with Some others. If I get really motivated I could make new jets but that would most likely not happen. I also saw a list of stock jetting for the dfos which seems very close to my dcnfs so they may be close. The vents will be on the smaller side for a 2.1 liter I'm building. It also looks like the venturis are not removable so that may be a problem. I read something years ago about the guys from empi going to weber and trying all the different carbs and the idfs and idas and dcnfs were the most suitable. I also recall something about berg saying that only the 42dcnfs had a progression circuit that was suitable for vws. So They may turn out to be a dead end or only suitable for a smaller motor. I got the Opel intake as well so if they turn out unsuitable I could sell them to an Opel owner if I could find one.i bought them to try something different. I'm not expecting a miracle and i think at the worst ill break even or even make a little money for other carbs.
 
Thanks ill see if they can help me out. I actually have a pair of 40 dcnfs for my vw already so ill see if the new ones fit. Did he have them in a full bodied car? I'm thinking they may be a little too wide for a bug. They should fit in a bus that I have though. The jets may be a problem though i saw something about jets may


He had them in a Baja Bug Rig- plenty of space!
they had a neat way of singing to you when he got into the pedal:))
 
Per Google. Application is 1969 Opel Rekord Sprint, 4 cyl. See ebay for German lang ad, 400 Euros. Not find any manuals. Ref "dellorto.com.uk."
FYI. Also wikipedia
 
Looks like jets are the same as some other more common webers so they should be easy enough to get. But it seems the bolt pattern and bore spacing are a little different from dcnfs but should be able to fit dcnf manifolds with a little work.
 
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