Throttle Shaft Tab, for 40 & 44 IDF & HPMX Carbs, Each

OVERVIEW

When you are pushing your air-cooled Volkswagen to the limit, every minor component under the hood plays a vital role in maintaining the integrity of your engine''s performance and safety. The EMPI Throttle Shaft Tab is a small but indispensable safety feature designed specifically for 40 and 44 IDF Weber-style and HPMX carburetors. In the high-vibration environment of a classic flat-four boxer engine, hardware has a natural tendency to vibrate loose over time. This lock tab acts as a mechanical fail-safe, wrapping around the throttle shaft nut to ensure that your carb linkage stays exactly where it belongs. Whether you are navigating a treacherous off-road trail in a Baja Bug or cruising the coastline in a vintage Karmann Ghia, having a secure throttle assembly is the difference between a smooth ride and a potentially dangerous mechanical failure caused by a backed-off nut.

Restoring or maintaining a set of performance carburetors requires attention to the finest details, and all too often, these throttle shaft tabs are overlooked or reused until they become brittle and snap. These tabs are designed to be bent over the flats of the nut, creating a physical barrier that prevents rotation. After several rebuilds or adjustments, the metal fatigues, losing its tension and its ability to lock effectively. This genuine EMPI replacement part ensures that your 40/44 IDF or HPMX series carburetors are serviced to the highest standards. Sold individually, these tabs are a low-cost insurance policy for your dual-carb setup, providing the peace of mind that your throttle synchronization and return will remain consistent through thousands of miles of driving.

FITMENT

This throttle shaft tab is designed for use with performance dual carburetor setups on the following vehicles equipped with Weber IDF or EMPI HPMX carburetors:

• Volkswagen Type 1: Beetle, Bug, and Super Beetle (All Years)
• Volkswagen Type 2: Bus, Transporter, Kombi, and Microbus (1950-1979)
• Volkswagen Type 3: Fastback, Squareback, and Notchback
• Volkswagen Karmann Ghia: All Years
• Volkswagen Thing: Type 181
• Porsche 356 & 912: Models converted to Weber IDF or EMPI HPMX systems
• Custom Builds: Sand rails, Dunebuggies, and Baja Bugs using 40/44/48 IDF or HPMX carburetors

SPECS

Technical specifications and dimensions for the EMPI Throttle Shaft Tab:

• Application: Fits Weber 40 IDF, 44 IDF, and 48 IDF series carburetors.
• Secondary Application: Fits EMPI 40 HPMX and 44 HPMX series carburetors.
• Material: High-tensile stamped steel for durability and flexibility.
• Finish: Zinc-plated for superior corrosion resistance and longevity.
• Function: Mechanical locking tab for throttle shaft end-nuts.
• Quantity: Sold Each (two required per carburetor, four per dual-carb engine).
• Part Number: 43-6414-0.

PRO TIPS

1. Always Replace, Never Reuse

The metal used in these lock tabs is designed to be bent once or twice at most. Every time you flatten the tab to remove the nut and then bend it back to lock it, the grain of the steel weakens. To prevent the tab from snapping off due to engine vibration, we always recommend installing a fresh tab every time you disassemble your throttle linkage or perform a deep cleaning of your carburetors. It is a small investment that prevents the catastrophic scenario of a nut falling into the engine bay or jammed linkage.

2. Proper Bending Technique

When securing the tab, use a small flat-head screwdriver or a pair of needle-nose pliers to start the bend, then finish it with a firm press. You want the tab to be flush against at least one flat side of the nut. Avoid over-hammering the tab, as this can put unnecessary side-load on the throttle shaft bearings. A snug, firm fold is all that is required to keep the nut from rotating. Ensure the tab does not protrude in a way that interferes with the full arc of the throttle lever or the synchronization linkage.

3. Check Shaft Alignment During Installation

Before you lock the tab down, ensure that your throttle shaft is centered and that there is no excessive end-play. If the shaft has moved too far to one side, it can cause the butterfly valves to rub against the carburetor bores, leading to a "sticking" throttle or erratic idle. Once the shaft is perfectly centered and the nut is torqued to the manufacturer''s specifications, fold the tab into place. This ensures that your mechanical settings are "frozen" in the optimal position for synchronized performance across both carburetors.