Technical TWIN CARB Question AGAIN !!!...

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Technical TWIN CARB Question AGAIN !!!...


New member
Mar 4, 2006
HI All,

I have been searching the net and ebay for a manifold and the corresponding carbs that will sit on it.

I have seen 2 variations so far (Alquati and Sprint) I have noticed that they can take different carbs (is this true, or am i wrong? )

Are there other options i can chose, or am i stack with the above 2 ???

Can someone give a table stating :
  • Intake Manifold (for dual carbs) , Make (model) that fit the X1/9
  • Carb model that will sit on manifold

Also can you describe the difference of these carbs ???

Sorry to bother you with the same question, but if you can tell me what carbs fit what manifold, i might be able to get some carbs for free from my uncle and just buy the manifold.

dont want to spend more money on the manifold-carb setup than what i spent for the car :bang: :D (y)

Thanks all,

the 2 you mentioned are good manifolds there are a few other types out there, but id stick w/ one of those...unless you score a FAZA(only seen 1 come up in the last 4-5 months & was a single DCNF intake) Now about what carb fits what intake......well its kinda self explanitory a twin DCNF will work w/ DCNF's but only DCNF's and so on for other carbs . just read first and you wont go wrong.
Last edited:
gserghiou said:
I have seen 2 variations so far (Alquati and Sprint) I have noticed that they can take different carbs (is this true, or am i wrong? )

…you’re wrong :p (though I suppose there must be some exceptions). Inlet manifolds are built for specific carb’s (as murcielagoGTR stated above). The two common types of “go fast” carb’s used on X1/9s are DCOE and DCNF; DCNF being the more prevalent as they require no modification to the structure of the car (for clearance). Of the DCNF manifolds there are three variations (for the 128 series motors), ones designed for the FIAT 128, ones designed for the X1/9 and those which are “fudged” to work with both. This is because the engines in X1/9s and 128s sit at very different inclinations and the manifold should allow the carb’s to sit level or they won’t operate properly.
yeah to add to the above comment, if im not mistaken the engine in an X1/9 is tilted foward 11 degreese thust the manifolds you'll find that say they are for 128/ x1/9 are more than likely wrong as they make the carbs sit at an angle. find one that states twin-carb manifold for x1/9.but as mentioned for the DCOE's there will be some work involved. but if you want a twin setup on the fly then go the DCNF way, it cost's less and bolts right up. have fun & good luck
There are actually three main variations of twin carburettor used for these applications, the DCNF, the DCOE and the IDF.

All use very different manifolds, and all three types are also available to suit the different engine inclinations of both the 128 (20 degree tilt) and X19 (11 degree tilt), and to add to that, there are several manufacturers, some of whom make one D/D manifold to suit both applications, and the carbs don't end up vertical as Mr Weber intended them to.

As prevoiusly stated, DCOE (sidedraft) will need sheetmetal mods, as the carbs will want to occupy the rear boot (trunk) space

DCNF and IDF are both downdraft carbs, and use very different manifolds.

DCNF works best IMO, as the bore spacing of the DCNF is almost identical to the port spacing in the cylinder head and the manifold ports are nice and straight. With the IDF's, the bore spacing is quite a bit wider, and a couple of the ports end up with quite a twist, as you can see in the pics.

DCNF definitely work the best on the street.



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