Single 40 Carburetor Kit, HPMX By EMPI

OVERVIEW

If you''re looking to wake up your air-cooled engine without the complexity of a dual-carburetor synchronized setup, the EMPI Single 40 HPMX Carburetor Kit is the ultimate solution for the street-driven Volkswagen. This kit is designed for the VW enthusiast who demands increased throttle response and a significant bump in mid-range torque while keeping maintenance straightforward. By utilizing a single, centrally mounted 40mm HPMX carburetor, you eliminate the need for constant balancing between two banks of cylinders, making it an ideal choice for daily drivers, weekend cruisers, and heavy-duty off-road builds that require reliable, consistent fueling across all RPM ranges.

Every component in this EMPI kit is engineered to provide a seamless transition from your stock, restrictive 34-PICT carburetor to a high-performance venturi-style system. The kit features a high-flow aluminum center-section intake manifold that optimizes air-to-fuel distribution to your dual-port heads. To ensure smooth operation, EMPI includes an aircraft-style heim joint linkage system that provides a crisp, mechanical feel at the pedalvastly superior to the flimsy stock linkage rods. Finished off with a classic chrome air cleaner and a high-efficiency element, this kit doesn''t just perform better; it transforms your engine bay with a professional, high-performance aesthetic that stays true to the air-cooled heritage.

FITMENT

This kit is designed specifically for Type 1 based dual-port engines (1600cc and larger). Please note that body clearance may vary on certain models, particularly with engine firewalls.

• Volkswagen Beetle: 1966-1977 (Standard)
• Volkswagen Super Beetle: 1971-1979
• Volkswagen Karmann Ghia: 1966-1974
• Volkswagen Bus (Type 2): 1963-1971 (With 1600cc Dual Port Engine)
• Volkswagen Thing (Type 181): 1973-1974
• Custom Dune Buggies & Sand Rails: Any Type 1 Dual Port Configuration

SPECS

• Carburetor Model: EMPI HPMX 40mm (Weber IDF Style)
• Main Venturi Size: 28mm (Pre-installed)
• Intake Manifold: Isolated Aluminum Center Mount
• Linkage Type: Aircraft-grade Heim Joint Rod Linkage
• Air Cleaner: Rectangular Chrome Housing with High-Flow Element
• Jetting Compatibility: Fully compatible with all Weber IDF series jets
• Fuel Inlet: Standard barbed fitting for 1/4 inch or 5mm fuel line
• Includes: Carburetor, Intake Manifold, Linkage, Gaskets, and Mounting Hardware
• Shipping Weight: 12.6 lbs

PRO TIPS

1. Fuel Pressure Management is Critical

One of the most common mistakes when installing an HPMX or Weber-style carburetor is over-pressuring the needle and seat. Stock VW fuel pumps can sometimes pulse higher than the required 2.5 to 3.5 PSI that these carburetors prefer. We highly recommend installing a high-quality fuel pressure regulator between your pump and the carb. If you exceed 3.5 PSI, you risk flooding the bowls, causing poor idle quality, or even "puking" fuel out of the top of the carburetor, which is a significant fire hazard.

2. Don''t Skip the Intake Manifold Heat

Because this is a single-carburetor setup, the fuel-air mixture has a long distance to travel from the center of the engine to the cylinder heads. In cooler climates or humid conditions, the intake manifold can "ice up" due to the refrigeration effect of atomized fuel. Always ensure your exhaust system has functional heat riser flanges and that they are properly connected to the intake manifold. This pre-heats the aluminum and prevents fuel from puddling or condensing on the inner walls of the intake, ensuring a much smoother idle and better cold-start drivability.

3. Fine-Tune Your Jetting for Your Altitude

While EMPI kits come with "baseline" jetting that works for many 1600cc to 1776cc engines at sea level, every engine is a different animal. If you experience a "flat spot" just off-idle, you may need to go up one size on your idle jets. Conversely, if you live in a high-altitude area like Denver, you will likely need to lean out the main jets. Since the HPMX uses standard Weber IDF jets, tuning is easy and parts are readily available. Always check your spark plug color after the first 50 miles to ensure you aren''t running too lean or too rich.