JayCee Billet Venturies, for 44 IDF & HPMX Carbs, 36mm

OVERVIEW

When it comes to fine-tuning your high-performance air-cooled engine, the venturi is the heart of your carburetor''s signal. These JayCee 36mm Billet Venturis are engineered to replace the standard, often inconsistent cast units found in Weber 44 IDF and EMPI HPMX carburetors. While factory cast venturis frequently suffer from rough surface finishes, casting flash, and slight out-of-round bores, JayCee manufactures these in-house from premium 6061 billet aluminum. By utilizing precision CNC machining, JayCee ensures a perfectly concentric taper and a glass-smooth finish that significantly reduces intake turbulence. This level of precision provides a much stronger and cleaner vacuum signal to the main discharge nozzle, resulting in crisper throttle response, the elimination of common "flat spots," and more predictable tuning across your entire power band.

Choosing the 36mm sizing for a 44mm carburetor body is a strategic move for the serious VW enthusiast looking to maximize mid-to-high RPM airflow without sacrificing bottom-end driveability. This specific size is widely considered the "sweet spot" for performance street engines ranging from 1915cc up to 2332cc, where high-velocity airflow is critical for peak horsepower. JayCee is a legendary name in the Volkswagen racing community, and their commitment to quality is evident in these components. Whether you are building a weekend canyon carver, a heavy-duty off-road rail, or a dedicated drag Beetle, these billet venturis provide the consistency and flow characteristics needed to get the absolute most out of your induction system. Stop struggling with the limitations of mass-produced cast parts and upgrade to the precision engineering that only billet aluminum can provide.

FITMENT

These billet venturis are designed specifically for use in dual-carburetor applications utilizing 44mm bores. They are compatible with the following models and configurations:

• Volkswagen Beetle: All years equipped with dual Weber 44 IDF or EMPI 44 HPMX carburetors.
• Volkswagen Karmann Ghia: All years utilizing 44mm performance carburetor upgrades.
• Volkswagen Bus (Type 2): Split-window and Bay-window models with performance upright or pancake engines running 44 IDF/HPMX setups.
• Volkswagen Type 3: Notchback, Squareback, and Fastback models with dual 44mm carburetor kits.
• Volkswagen Thing (Type 181): Performance-modified engines requiring 44mm carburation.
• Custom Engines: Ideal for 1776cc, 1835cc, 1915cc, 2017cc, 2110cc, 2180cc, 2276cc, and 2332cc air-cooled powerplants.
• Carburetor Compatibility: Genuine Weber 44 IDF, EMPI 44 HPMX, and various 44mm IDF clones.

SPECS

Detailed technical specifications for the JayCee JC43370 Billet Venturis:

• Material: High-grade 6061-T6 Billet Aluminum.
• Internal Diameter: 36mm (Precision Bored).
• External Diameter: Sized for 44mm Carburetor Main Bores.
• Finish: Raw Machined Billet for maximum airflow efficiency.
• Quantity: Complete set of 4 (Required for two dual-throat carburetors).
• Manufacturing Process: 100% CNC Machined in the USA.
• Compatibility: Weber 44 IDF and EMPI 44 HPMX Series.
• Weight: Approximately 0.4 lbs for the complete set.

PRO TIPS

1. Adjust Your Jetting for Increased Airflow

When you upgrade to a 36mm venturi from a smaller size (like a 32mm or 34mm), you are significantly increasing the volume of air passing through the carburetor. Because of this, you will almost certainly need to increase your main jet size to maintain the correct air-to-fuel ratio. A larger venturi reduces the vacuum signal slightly at lower RPMs while increasing flow at high RPMs. We recommend starting with a main jet that is approximately 4 to 4.5 times the venturi size as a baseline. For a 36mm venturi, a 150 or 155 main jet is a common starting point, but always use a wideband O2 sensor to verify your specific engine''s requirements under load.

2. Inspect Carburetor Bodies for Proper Seating

Before installing your new JayCee Billet Venturis, take a moment to inspect the internal bores of your carburetor bodies. Cast carburetor bodies can sometimes have small burrs or imperfections where the venturi sits. Since these billet units are machined to extremely tight tolerances, any debris or casting flash in the carb body can prevent the venturi from seating perfectly flat. We suggest cleaning the bores thoroughly with carburetor cleaner and a soft nylon brush. If you encounter resistance during installation, do not force the venturi; instead, check for high spots in the carburetor casting and lightly smooth them out with fine-grit sandpaper if necessary.

3. Match Venturi Size to Your Camshaft and Heads

While it is tempting to go with the largest venturi possible, performance is all about the "package." A 36mm venturi is excellent for high-performance street engines, but it works best when paired with cylinder heads that have been ported and a camshaft with enough duration to utilize the extra flow (such as an Engle W-120 or W-125). If you are running stock valves and a mild "cheater" cam, a 36mm venturi might actually slow down your intake velocity too much at low RPMs, leading to a loss of bottom-end torque. Always ensure your intake tract, from the air filter down to the intake valve, is sized appropriately for your engine''s displacement and intended RPM range for the best driving experience.