Weber DCNF set up for 2110?

[PlanB]

Finishing up a 2110 type 3 motor that I plan on road racing ('73 Fastback/DE car) and am looking for advice on setting up the 'Berg Special' 42 DCNF's that came on the original engine that I rebuilt.

Looking for advice on a starting point set-up of these weber carbs / jetting suggestions, venturi size, etc. specifically for road racing.

2110cc, 40x36 heads, web cam 110, 1:1 rockers, 1 5/8" exhaust, 9:2 CR

Thanks!

[DarthWeber]

You might consider going with different carbs (Dellorto 40DRLA's) for a pure road race application. Since you have the Berg Specials have you called the Bergs and asked for set up info? I think one thing they will recommend is the ball type fuel inlet valve, rather than needle valve type. The ball type helps keep the fuel level in the float bowl more stable which can be a problem with DCNF's (that and they have a very small float bowl) in high G turns leading to a lean out condition.
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[luckystiff]

theres simple cures for the "lean out" condition that seems over exagerated anyhow. i think it was BRENT that posted the tech...ken....
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ITMC
Secret Service

[DarthWeber]

[PlanB]

[subtaf]

Where is the best place to buy the parts to convert to the ball type inlet valve?

I have twin 40DCNF's on my 2019cc type 4 with a cam similar to the 110 for a type 1. The chokes were far too small (28mm). But pulled real hard from 2500 - 5000 rpm. It couldn't rev any more than 5500rpm in top gear with these chokes though.

I'm running 34mm chokes now but with a stock motor while the stroker is getting a freshen up. 34mm seems to big for the stock motor with a better exhaust.
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59 Split Panel van project.
2109cc 75 micro bus
89 T3 4WD Syncro
Zero Type 3's as yet.

[spencerfvee]

i two just picked up a set of 40 dcnf webers i have 32 venturis with 220 airs and 125 mains i never liked 220 airs and the mains seem to be to small for my 2180 motor. i have not put the 40s on my motor yet .they need rebuilt first . i had a set years ago and liked them. i to would like to know who sells jets for the dcnf weber carbs spencerfvee

[DarthWeber]

Jets, venturis and replacement parts can be sourced from Pierce Manifolds
http://www.piercemanifolds.com/
or AirCooledEngineering or AC.Net.
Gene Berg always toted the DCNF flag with their Berg Special carbs. They might have some DCNF parts and also the inlet ball valves. You never know, it's probably a 50/50 chance they'll have something in stock nowadays.
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[spencerfvee]

wow thanks darth that web site rocks . darth for a starter what size mains and air jets would you start with for a 2180 motor with ported 40mm by 35 mm valves heads. engle v26 cam the carbs have 32mm venturis. 45 pump jets .50 idl. jets thanks spencerfvee

[subtaf]

Hi spencefvee,

I have 34 venturies in my 40's with my 2109 type 4 which I run in a bus. These are probably a little too big and I'm thinking I should be running 32 venturies in mine. My 34 vents would probably suit your 2180 and your 32 vents would suit mine. Interested in a swap?

I think postage is on $10 or so to here.
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59 Split Panel van project.
2109cc 75 micro bus
89 T3 4WD Syncro
Zero Type 3's as yet.

[PlanB]

[subtaf]

No problem. At least you will get the size you need anyway. I'll get around to advertising these eventually.
_________________
59 Split Panel van project.
2109cc 75 micro bus
89 T3 4WD Syncro
Zero Type 3's as yet.

[Brent]

[VerySquareBack]

I've observed this topic, and wanted to add some more. I've been running a pair of DCNFs for 40 years on a 1640 and have got the mileage up to 33 with no lean spots. The set-up has been with 32 Venturi, but the air and fuel jets, and e tubes are not specific to any one formula. My biggest observation is that a Air/Fuel meter is manditory along with a CH Temp guage. I've seen a 50 degree increase within 2 miles after a jet change. A person has to use caution and be very careful.
Carbs can be very smooth yet way off proper mixture and until they are very lean don't make their condition known. Lately I've started making my own emulsion tubes that have allowed the main fuel jets to drop from 145 to 119 and run at a steady 13:1 at mid speed and top. The transition from the idle circuit is still difficult to get right.
On the issue lean mixture on cornering consider this: on the Ferrari motors the DCNF is mounted across the motor with the float bowl in front. On acceleration the top surface of the fuel tilts up at the back which is over the fuel circuit richening the mixture. On our VWs the carbs sit sideways, so the inside carb goes rich as the outer carb goes lean. On the other hand, the IDF/IDA have the fuel bowl between the barrels and should lean the front barrels on acceleration. Oh well, that's carbs.[/url]

[wheel607]