Single DCNF manifolds and NOS 36 DCNVA carbs

fiatfactory

fiatfactory

Steve Cecchele
I've just had a few '74 style (26mm ports) X19 inlet manifolds modified to take a single DCNF (or variant) carburettor. I just got them back from my friendly machinist today, and still have to do a little cleanup and tap the stud holes, but I thought I'd take a few pictures to show everyone.



I am offering these complete with a NEW (NOS) WEBER 36DCNVA carb. A DCNVA carb is just like a DCNF except it has a strangler flap type of choke setup (rather than the enrichment tube type choke of the DCNF)









Very simple setup and install, with most of the performance of twin carbs, but without the balancing and setup issues and of course less expense. These carbs already have a ported vacuum fitting, so can be easily used with a vacuum advance style distributor, giving a good balance of performance and economy.

Complete carb / manifold setup will be fitted with a carby linkage arm to suit X19 style linkage rod, phenolic spacer and gaskets, modified manifold and a NEW (NOS) 36 DCNVA carb for just $450au plus postage.

I can also supply overhauled euro 1500/1300 cylinder heads (8 new guides/3 angle cut seats/ 8 new TRW valves/ resurfaced with a late model combustion chamber - with no full circular recess so an instant compression bump with no head milling required) complete with new oversize inlet seats (34mm throat) and new 37.5mm inlet valves already fitted for a complete street performance package. You get a modified overhauled head, a single DCNF inlet manifold, a (used) twin out euro 1500 exhaust manifold and a NEW 36DCNVA carburettor...make your wheezy US spec engine come alive...please enquire by email or PM
 
Wow, great deal

This is what I use to have on my old DP car. Really a bullet proof setup.

Great price.

Eric
 
Question for those in the US autox scene. Is this a legal setup for use in GP on the 1500? The rules make allowance for a 36DCNF but I have only seen these mounted with a simple bolt on adapter to the stock intake. The rules just say "manifold adapter", does that include a welded on adapter that turns the carb 90deg?
 
It's a gray area of the specs

I have seen racers running in SCCA National competition with welded plate adapters, but as is typical for SCCA, the rules interpretation will vary, and the only rule interpretation that matters is the one from the chief of tech at a given race.

Technically, the only requirement is that the adapter must be within a max thinkness spec. It may be implied that the adapter is a flat plate, though it is not explicit. It is also possible that some tech inspector will interpret the term "adaptor" as something removable, though the means of attachment is not specified.

Paul
 
I agree...

I think most inspectors tend to read the manifold adapter as some type of riser plate or other product to enhance the fuel/air mixture.

Eric
 
Technically to fit a DCNF style carb to the stock manifold doesn't require an adaptor at all.. the DMTR and DCNF bases are very similar and a simple repositioning of a couple of stud holes would suffice ie weld up the old ones and drill and tap a couple of new stud holes (as per in the attached pictures) BUT, the DCNF (or variant) would then sit (technically) incorrectly as the float pin axis would be 90 degrees away from what Mr Eduardo Weber designed it for...and the linkage is all in the wrong place for a simple hook up...




I had these manifolds made up as I came across three NOS 36DCNVA's and thought they would work nicely on a mild sohc engine build. I've used single 40 DCNF's a few times (with similarly modified manifolds and also Alquati and Sprint manifolds so the carbs were correctly positioned and the linkage hook up was simple) and the results were always great.
 
I x 36DCNVA and manifold setup and the spare manifold I had made already sold, so just two manifold and carby setups left.

If there is enough demand I can have another batch of manifolds made, manifolds by themselves work out to $200au each, postage to the USA is another $60au.

SteveC
 
Thanks Steve NICE manifold!

I cleaned it up, ported it and painted it, can't wait to try it out
_IGP1271.JPG
 
Your welcome Chris, thanks for the business... that does look nice in the crinkle black finish, and with the vintage Bayless "meaner cleaner" too.

SteveC
 
Heads.

fiatfactory said:
I can also supply overhauled euro 1500/1300 cylinder heads (8 new guides/3 angle cut seats/ 8 new TRW valves/ resurfaced with a late model combustion chamber - with no full circular recess so an instant compression bump with no head milling required) complete with new oversize inlet seats (34mm throat) and new 37.5mm inlet valves already fitted for a complete street performance package.
Click to expand...

Hey Steve,

do you have these heads with the cut out for fuel injection? Do you have a 14 bolt version?

Cheers,
Dom.
 
Hi Dom,

no the EFI heads are pretty scarce here in Australia, same with plain (no cut out) 14 bolt heads... not too many models were sold here with them fitted.

As it happens I'm currently prepping a head for Brian McKillop (from here on this forum) that's a 14 bolt (was from an SPI regata 85Sie) but it's a non cut out type. Hopefully (if my machinist has it done) I'll be picking it up on Friday... he's gone for new 37.5 inlet valves on new oversize seats (34.2mm throat) and 8 new cast iron guides (to keep the cost down) with Serdi cut three angle seats and back cuts on the inlet valves... so I'll post some pictures when I get it back.

Then I'll be trimming back the inlet guides, mildly porting the valve bowls, deshrouding and CCing the chambers, and then matching the head to the euro 1500 carb inlet manifold he'll be using...along with a euro 1500 24/68 cam, and a twin out maniold and front pipe... so it should flow really nicely, and with totally factory parts, all from the Fiat parts bins.

SteveC
 
Well Domenic has put his hand up for a complete carby / manifold package for his series 1 X19 here in Australia... this means there is just one setup left.

I won't have any more 36DCNVA's to sell as these were from a dealer closeout in the UK, so I doubt they will ever be available at this price again. if your considering something like this to upgrade your X19, I suggest you get in quick...

If your interested in a manifold only, I will definitely be getting more made up, I just need to find a few more standard manifolds to get a batch of four done at once to make it economical.

SteveC
 
GP rules regarding DCNF carb

3. Stock or permitted alternate downdraft carburetor(s) can use an
adaptor plate and/or a spacer in addition to any stock spacer,
between the carburetor(s) and the intake manifold. Material for
the adaptor plate and spacer is unrestricted. No adaptor plate
or spacer can serve any purpose other than to space out, or
mate the carburetor(s) to the permitted intake manifold. The
adapter or spacer cannot change the carburetor(s) orientation.
Adaptors and spacers can have a bore larger than the throttle
bore of the stock or permitted alternate carburetor(s). The
maximum thickness for the adapter, spacer, stock spacer or
combination of all is 1.25 inches. For the purpose of these rules
an isolator is a spacer

I read that to mean the spacer/adapter cannot change the orientation of the carb, does that mean these manifolds do not conform to the rules for GP?
 
Last edited:
Orientation could mean to change from down-draft to side-draft?? as it doesn't specifically mention the orientation of float bowl or throttle shafts??

These were never meant to be GP legal, just an affordable upgrade.

It would be nice to have a definative ruling though, for those that do run in SCCA GP class... maybe someone can pose the question with some pictures to an SCCA scruitineer?

SteveC
 
I'm thinking about having some more of these single DCNF style manifolds made (modified stock items) or the second option is to have some brand new items cast...

I recently had a NOS genuine 128 Alquati modified to suit the tilt of the X19 (welded the stud holes up, remachined the top face and redrilled and tapped the carb mount holes) so I have a sample to shop out to a foundry... I also plan on flow testing and modifying the sample manifold for best and most even flow to all cylinders

The only problem with casting them up, is I need to do a batch of at least 100 to make it economically viable, and that's a fair chunk of $$ to outlay.

No commitment required, but how about a show of hands of people who would be interested in a new Alquati copy, made at the correct angle to suit an X19....

At an educated guess, the retail would be around the $350au mark for a new manifold... compared to the around $250au figure I could sell modified stock manifolds for...(as I now need to go out and buy up used manifolds, the first four were made from manifolds I had)

What would people prefer? Is the 30% higher cost of a new manifold going to kill the deal?

I've also just bought 25 more carbs too... so manifold and carb sets will be available again too...or manifolds by themselves if you have a carb already, or want to go 40/42/44DCNF.

SteveC
 
You must log in or register to reply here.
Back
Top