PMO Carburetors

PMO Carburettors – High-Flow, High-Precision Performance Carburetor Systems for Porsche Engines

PMO carburettors are engineered from the ground up as state-of-the-art performance carburetor systems, created specifically to surpass the airflow capability, build quality and tuning refinement of traditional three-barrel Weber units. Designed around a large 50mm throttle plate and then expertly downsized into 46mm and 40mm options, PMO carburettors offer exceptional intake efficiency, precise throttle response and superior mixture control—ideal for classic Porsche air-cooled performance engines.

Manufactured from A-356 aircraft-grade aluminium using permanent mold casting, PMO units achieve aerospace-level consistency and durability, far stronger and more stable than traditional die-cast pot-metal carburettors. High-velocity airflow, improved fuel atomisation and unmatched adjustability make PMO carburettors the premium choice for enthusiasts, restorers and performance tuners.

Why PMO Carburettors Outperform Traditional Weber Carburettors

PMO engineered their carburettors from scratch with performance as the primary goal. Key design features include:

• Larger main barrels in the throttle body for increased air entry
  
• Tapered top covers improving airflow velocity and reducing turbulence
  
• Oversized tapered velocity stacks – Maintain high-speed airflow boost down to the auxiliary venturis
  
• Ball-bearing supported single throttle shaft – Smooth, precise and reliable throttle movement
  
• Replaceable idle air jets for fine idle control
  
• Float bowl sight glass for easy tuning and diagnostics
  
• Full range of venturis, jets & emulsion tubes for complete tuning flexibility
  
• Enhanced float bowl design for more consistent fuel levels
  
• Two sizes of auxiliary venturis for precise airflow control
  
• Heat-treated permanent mold castings for exceptional strength and stability

These features translate into greater airflow, faster throttle response, improved tuning precision and stronger performance across the RPM range.

What PMO Carburettors Do

PMO carburettors ensure precise control over air-fuel mixture and airflow delivery:

• Regulate airflow with optimised venturi and throttle geometry
  
• Improve throttle response through smooth bearing-supported shafts
  
• Enhance fuel atomisation for better combustion efficiency
  
• Support performance tuning with fully adjustable jets and emulsion tubes
  
• Increase engine breathing capacity, especially in high-revving applications
  
• Deliver smooth idle stability with replaceable idle air jets
  
• Provide consistent fuel delivery through improved float bowl design

The result is a crisp, powerful and responsive engine that breathes properly at every RPM.

Why Carburettors Fail Over Time

Even high-quality carburetor systems degrade due to heat, vibration, fuel contamination and age. Common failure points include:

• Worn throttle shafts, causing air leaks and inconsistent idle
  
• Warped castings in low-quality or ageing pot-metal carburettors
  
• Clogged jets or venturis from old fuel or debris
  
• Float bowl percolation, especially in hot climates or spirited use
  
• Vacuum leaks, producing unstable mixture and rough running
  
• Heat soak causing irregular fuel delivery or hot-start issues
  
• Corroded internal components, affecting tuning accuracy

These issues lead to hesitation, flat spots, rough idle, poor throttle response and reduced performance.

Why You Should Replace or Upgrade to PMO Carburettors

Installing high-flow, precision-built PMO carburettors ensures:

• Superior airflow and improved high-RPM breathing
• Smooth, accurate throttle modulation
• Stronger, more predictable tuning results
• Reduced heat-related issues due to better materials and engineering
• Long-term resistance to warping and distortion
• Faster and easier tuning with accessible jets and sight glass
• Better compatibility with performance camshafts, exhaust systems and high-compression builds

PMO carburettors deliver modern performance with classic Porsche character, making them an ideal upgrade for restorations, track builds and performance-enhanced air-cooled models.

Recommended Upgrade: PMO Carburetor Insulator Kit

PMO strongly recommends using their Carburetor Insulator Kit between the cylinder head and intake manifold.

Benefits:

• Reduces heat transfer to the float bowl
• Prevents fuel percolation and hot-start problems
• Includes insulators, gaskets and extended stainless head studs
• Essential for consistent performance in warm climates and track conditions

When ordering, include:

• Carburetor size
• Cylinder head type / model year
• Intake port diameter