Carburetion & Injection



From its inception the 911 engine was a high performance design, built around carburetion and tuned exhaust. In spite of all the "improvements" along the lines of fuel injection and emission control, the 911 with carburetors is still a good fit. Mechanical fuel injection was never totally successful on a street engine because of erratic mixture control and poor atomization at lower RPMs. CIS fuel injection is oriented towards emission control and, after 1974, is also coupled with restrictive exhaust system.

PMO is the original manufacturer of 911 carburetor conversions and we are the only company in the world dedicated exclusively to providing 911 Carburetor Conversions. We manufacture sixteen different manifolds for the 911. They are all of the highest quality; cast of prime, heat treated aluminum. Bore matching, porting-polishing is standard. No matter what 911 engine you may have, from 2.0 to 3.8 liters, we have the height, port combination and bottom flange shape to fit your application. For instance, our 2.7 CIS manifold has the correct 35mm port size and correct CIS shape bottom flange. Adding the CIS shape to the bottom flange of the manifold is a PMO innovation. This flange eliminates the need to weld and grind on the cylinder heads to fill the notches that are in the CIS ports. The 3.6 litre manifolds come with triangular flanges and insulators to bolt right up to the cylinder heads.

We started manufacturing linkage when the factory discontinued the Weber crossbar. Our crossbar uses the original Weber configuration and improvements include pressed-in, fully machined bearings, one piece throttle arm on the left side, replaceable hard ball pins, and heliarced assembly. The current factory Zenith crossbar has crimped bearings, two piece tack welded throttle arms on the left side, staked-in ball pins and brazed assembly. Our small bell crank has a solid silicon bronze bearing, one inch in length, whereas the factory bell crank is constructed with a hollow tube and two plastic bushings. Our short press rods are machined out of hex rod; the factory press rods are only a rod with a nut brazed in the middle.

The finest Air Cleaner element is the K & N. We have custom designed our own filter cases to accept the K & N elements. Our air cleaners come in two heights, one shorter for air conditioned cars. The short height element was manufactured specially for us by K & N. In turn we manufactured short velocity stacks for use in this unit. Our kits also include a K & N oil tank breather. To prevent hydrolock our kits now include the Watershield top cover assemblies.

Another innovation by PMO is our fuel pressure control unit. This enables you to retain your high pressure, high volume pump for use with the PMO Carburetors. Each pressure control unit has a built-in pressure gauge and is fully adjustable to set the fuel pressure while the engine is running. By retaining your stock high volume fuel pump in combination with our unit there is never a worry about your engine exceeding the capacity of a low pressure/low volume fuel pump.

Another standard item included in our kits is our heat insulator plates with longer studs. The purpose of these is to stop float bowl percolation which leads to flooding. Naturally, these come in sets custom fitted to your port size and flange configuration. High pressure fuel line and a full set of required gaskets are included. Also included are full and complete instructions. When you order a PMO kit all you need is your tools and time. Nothing is left to chance

We offer more 911 Carburetor Conversions than ANYONE else. Having experienced numerous combinations gives us a wide and varied knowledge of our specialty.

We manufacture a complete selection of venturis to provide the proper size for each application. Venturis are machined out of heat treated aluminum to an Aero-Space quality finish. The jetting and venturi combinations included in our kits have been worked out through years of experimentation on the road, track and dynamometer

Remember there is only one company that originated the 911 Carburetor Conversion Kit, manufactures all the necessary components to integrate the PMO carburetors to your engine, has the highest quality components all the way through, has the widest selection of 911 conversion kits, and has the most experience with 911 carburetor conversions. That company is PMO.