Pump Jet IDF, .55

EMPI Pump Jet IDF, .55 - 76210.055

Product Overview

The EMPI .55 Pump Jet is a precision-engineered component designed for Weber and EMPI IDF series carburetors. This jet plays a vital role in the acceleration circuit, delivering a metered shot of fuel to prevent hesitation when the throttle is opened. For aircooled VW enthusiasts looking to optimize engine response, the .55 size offers a slightly larger fuel volume than standard stock jets, making it ideal for performance-oriented builds.

VW Fitment and Compatibility

This pump jet is a direct fit for IDF style carburetors used on a wide range of Volkswagen applications. It is commonly utilized in dual-carburetor configurations on VW Beetles, Karmann Ghias, Type 2 Buses, and off-road Dune Buggies. It is compatible with EMPI HPMX and Weber IDF carburetors, ensuring your aircooled engine receives the precise fuel delivery required for high-performance driving conditions.

Pro Tech Tips for IDF Tuning

Tip 1: Solve Acceleration Hesitation. If your engine experiences a flat spot or stumble immediately after you step on the gas, it is often a sign of a lean condition in the acceleration circuit. Upgrading to a .55 pump jet provides a more robust fuel squirt to bridge the gap between the idle and main circuits, smoothing out your acceleration curve.

Tip 2: Verify Symmetrical Discharge. In dual-carburetor setups, it is crucial that the pump jets in both carburetors discharge fuel at the exact same time and in equal amounts. Use a graduated cylinder or a specialized measuring tool to check the CC output per stroke. Consistent fuel delivery across all barrels is the key to a balanced and vibration-free engine.

Tip 3: Inspect the Pump Jet O-Rings. Whenever you remove or replace a pump jet, always inspect the small O-ring on the jet carrier. A dried-out or cracked O-ring can allow fuel to leak past the jet rather than through it, causing inconsistent performance and potential tuning headaches. Always ensure a tight, leak-free seal for optimal throttle response.