Air Jet DGV, DFV, ICT, EPC 140

OVERVIEW

Achieving the perfect stoichiometric balance in your air-cooled engine requires more than just a "set it and forget it" mentality; it demands the precision that only high-quality calibration components can provide. The EMPI Air Jet for DGV, DFV, ICT, and EPC carburetors is a critical component for any enthusiast looking to master their fuel delivery system. In the world of Volkswagen performance, the air jet plays a vital role in the main metering circuit, acting as a bleed that mixes air with the fuel before it enters the venturi. This 140-sized jet is specifically designed to help you fine-tune the high-speed enrichment of your engine, ensuring that your air-fuel ratio remains consistent even as the RPMs climb. Whether you are running a classic Weber 34 ICT setup on a mild street 1600cc or a progressive DGV on a torquey 1914cc, having the correct air jet is the difference between a crisp, responsive throttle and a sluggish, rich-running disaster.

Precision-engineered by EMPI to meet the rigorous demands of Volkswagen performance tuning, this 140 air jet is the key to eliminating high-RPM stumbling and ensuring a smooth transition across your power band. Unlike inferior, off-brand jets that may have inconsistent orifice diameters, EMPI components are manufactured to exacting tolerances, providing you with the peace of mind that your tuning adjustments are accurate. These jets are essential for dialling in your carburetor to compensate for local elevation, humidity, and specific engine modifications like high-lift cams or free-flowing exhaust systems. By choosing the right air jet size, you can effectively "lean out" the high-speed circuit if your engine is currently running too rich at wide-open throttle, allowing for maximum horsepower extraction and improved fuel economy during spirited driving. Don''t settle for "close enough" when you can achieve perfection with genuine EMPI calibration parts.

FITMENT

This air jet is designed for use with the following carburetor models and air-cooled Volkswagen applications:

• Carburetor Models: Weber DGV, DFV, ICT series, and EMPI EPC series.
• Volkswagen Beetle: All years equipped with aftermarket ICT or Progressive carburetor conversions.
• Volkswagen Karmann Ghia: 1956-1974 models utilizing Weber or EMPI performance carburetors.
• Volkswagen Bus/Transporter: 1950-1979 Type 1 and Type 2 engines with compatible carburetor upgrades.
• Volkswagen Type 3 (Squareback, Fastback, Notchback): 1962-1973 with dual ICT or EPC carburetor kits.
• Volkswagen Thing (Type 181): 1973-1974 models upgraded for off-road or street performance.
• Custom Sand Rails and Manx Buggies: Any air-cooled upright engine utilizing the Weber-style DGV, DFV, ICT, or EPC platforms.

SPECS

Detailed technical specifications for the EMPI Air Jet 140:

• Jet Size: 140 (1.40mm Orifice).
• Material: High-grade solid brass for corrosion resistance and thermal stability.
• Compatibility: Fits DGV, DFV, ICT, and EPC carburetor bodies.
• Circuit Application: High-speed air correction circuit.
• Thread Type: Precision-cut threads for a secure, leak-free fit within the emulsion tube stack.
• Manufacturing Standard: CNC machined for exact flow rate consistency.
• Quantity: Sold individually (Each).
• Part Number: 77201.140.

PRO TIPS

Understanding the Inverse Relationship of Air Jets

One of the most common mistakes beginners make is assuming that a larger air jet makes the engine run richer, similar to how a main fuel jet works. In reality, the air jet has an inverse relationship with the fuel mixture. A larger air jet, such as moving from a 120 to a 140, actually introduces more air into the emulsion tube, which leans out the mixture at higher RPMs. If your spark plugs are showing a dark, sooty color after a high-speed run, or if the engine feels "lazy" at the top of the gear, stepping up to this 140 air jet can help lean out that top end and "clean up" the power delivery. Conversely, if you experience a high-speed lean pop or surging, you may need to go smaller. Always tune your main fuel jet first for the mid-range, then use the air jet to fine-tune the high-RPM slope.

The Importance of Clean Air and Proper Maintenance

Because the orifice of a 140 air jet is precision-drilled to exactly 1.40 millimeters, even the smallest speck of dust or debris can significantly alter your engine''s performance. When installing these jets, ensure your workspace is clinical. Never use a metal wire or a welding tip cleaner to clear a clogged jet, as the hardened metal will scratch the brass and permanently change the flow characteristics. Instead, always use pressurized aerosol carburetor cleaner followed by a blast of compressed air. Additionally, ensure you are running high-quality air filters; air jets are located at the top of the carburetor and are susceptible to sucking in fine particulates that bypass a poor-quality filter, which can lead to inconsistent AFR (Air-Fuel Ratio) readings.

Systematic Tuning with a Wideband O2 Sensor

To truly master the use of the 140 air jet, we highly recommend the use of a wideband O2 sensor and gauge. While "reading plugs" is a time-honored tradition in the air-cooled VW world, it only provides a snapshot of the engine''s condition. A wideband sensor allows you to see exactly what happens to your air-fuel ratio as the air jet comes into play. You will typically notice the air jet''s influence starting around 3,000 to 3,500 RPM. When testing the 140 jet, perform a "third-gear pull" from low RPM to redline. If you see the AFR start to dip into the 10:1 or 11:1 range (too rich) at high RPM, this 140 jet is the tool you need to bring that ratio back toward the ideal 12.5:1 or 13:1 for maximum power. Always change only one jet size at a time and document your results to build a tuning map for your specific engine build.