Genuine Weber carburetor parts - en - USD WEBER 40 DCOE main venturi choke tube 24/25/26/27/28/29/30/31/32/33/34/35/36 mm - en - USD

WEBER 40 DCOE main venturi choke tube 24/25/26/27/28/29/30/31/32/33/34/35/36 mm

$ 16.8

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Part number: 72302

Made in: EU

Compatible with:

Family: WEBER

38 DCOE 59/60 (2 pcs)

40 DCOE early type (2 pcs)

40 DCOE emission model (2 pcs)

40 DCOE late type (2 pcs)

Family: DCOE

38 DCOE 110-111 - pn: 72302.300 (2 pcs)

38 DCOE 110M-111M - pn: 72302.300 (2 pcs)

38 DCOE 59-60 - pn: 34926.002 (2 pcs)

40 DCOE 106-107 - pn: 72302.300 (2 pcs)

40 DCOE 112-113 - pn: 72302.320 (2 pcs)

40 DCOE 120-121 - pn: 72302.320 (2 pcs)

40 DCOE 151 - pn: 72302.300 (2 pcs)

40 DCOE 44-45 - pn: 34926.002 (2 pcs)

40 DCOE 72-73 - pn: 34926.002 (2 pcs)

40 DCOE 76-77 - pn: 34926.002 (2 pcs)

40 DCOE 80-81 - pn: 34926.002 (2 pcs)

40 DCOE 88-89 - pn: 72302.340 (2 pcs)

40 DCOE 92-93 - pn: 72302.300 (2 pcs)

WEBER 40 DCOE Main Venturi Choke Tube 24–36 mm – MPN 72302

High-quality main venturi (choke tube) for Weber 40 DCOE carburetors, manufactured in the EU with an emphasis on dimensional accuracy, consistent quality, and a smooth internal airflow surface.

The main venturi establishes the primary airflow restriction through each carburetor barrel. Its internal diameter and profile determine air velocity through the choke and influence the pressure signal acting on the auxiliary venturi and main fuel circuit. Venturi size therefore has a direct effect on fuel draw, throttle response, mixture behaviour, and the engine's airflow capacity at higher rpm.

Available sizes are 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, and 36 mm.

Even sizes: 24, 26, 28, 30, 32, 34, and 36 mm.
Odd sizes: 25, 27, 29, 31, 33, and 35 mm.

Price is for one venturi in the selected size. Leave the required size in the order message.

The carefully finished and smooth internal surface helps maintain clean, unrestricted airflow through the choke tube and reduces unnecessary flow disturbance. Venturi quality and surface finish are particularly important in performance applications, where consistent airflow between individual carburetor barrels contributes to predictable carburetor calibration.

This venturi is designed with two locating-pin holes, allowing correct installation in either the left or right carburetor barrel. The locating pin should be fitted into the appropriate hole according to the venturi position. This configuration also provides compatibility with short “ALFA” type pump jets.

The main venturi is only one part of the complete carburetor airflow and fuel-metering system. Auxiliary venturi design and condition, air-horn geometry, throttle-shaft profile, throttle-plate edges, pump-jet configuration, emulsion tubes, main jets, air correctors, and overall carburetor calibration can all affect final engine response and airflow characteristics.

Suitable for carburetor rebuilding, restoration, performance tuning, or replacement of worn, damaged, modified, or missing original venturis.

Reference/MPN: 72302.

Technical role: Main venturi (choke tube) for Weber 40 DCOE carburetors, establishing the primary airflow restriction and controlling the airflow signal through each barrel.

Service relevance: Changing venturi diameter alters both airflow capacity and carburetor signal strength and may require corresponding changes to the fuel and air jetting.

What Is Included

One Weber 40 DCOE main venturi (choke tube) in the selected size
Made in the EU to high quality standards with a smooth internal airflow surface.

We also sell set of four here

Tuning Tips

Venturi diameter is one of the most important variables when setting up a Weber DCOE carburetor. The correct size depends on engine displacement, cylinder capacity, cylinder-head airflow, camshaft specification, intended operating rpm, and the balance required between low-speed response and maximum airflow.

A smaller venturi increases air velocity and generally produces a stronger fuel-metering signal. This can improve low- and mid-range response, progression, and drivability, but may restrict airflow at higher engine speeds.
A larger venturi increases maximum airflow capacity and can support greater high-rpm power potential, but reduces air velocity and signal strength at lower engine speeds. If the venturi is too large for the engine combination, throttle response and fuel metering may become less responsive.
When changing venturi diameter, do not assume the existing jetting will remain correct. Main jets, air correctors, emulsion tubes, idle jets, and other calibration components may require adjustment.
Use the same venturi diameter in all barrels serving the same engine unless the carburetion system has been designed specifically for a different configuration.
For performance tuning, make venturi and jetting changes systematically and evaluate the result under load. Wideband lambda / AFR measurement is strongly recommended when establishing final fuel calibration.
Do not select the largest possible venturi purely for maximum airflow. The best result normally comes from selecting a choke size that maintains sufficient air velocity and fuel signal throughout the engine's intended operating range.

Important Fitment Note

Verify that your carburetor is a genuine Weber 40 DCOE-pattern carburetor and confirm the required choke-tube diameter before ordering.

Check the MPN 72302 reference, size marking, overall venturi profile, locating-pin arrangement, retaining/interface features, and seating relationship inside the carburetor. Compare the replacement venturi directly with the removed part whenever possible rather than relying solely on vehicle make, model, or engine application.

Also confirm compatibility with the auxiliary venturi and pump-jet arrangement. When using short “ALFA” type pump jets, the locating pin must be installed in the correct left- or right-side hole according to the venturi position within the carburetor.

Compare the removed venturi with the selected size, profile, locating features, and seating geometry before installation, especially when using short “ALFA” type pump jets.

What you see is what you get

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