Production Porsche Carburetor Chronology
The carburetors Porsche fitted to 356, 912, and early 911 engines — and how they evolved.
Early 1950s — Pre-A and Early A
Gmünd cars used carbs made by Huff, with a 26mm throat. We have restored only one set over the past 20 years — they are very scarce.
Stuttgart cars started using the Solex 32PBJ (also referred to as PBI) in 1950. In 1951 they added the super engine and the 40 single barrel carburetors for Carrera. The 32's had a 32mm throat, and a side-mounted cold start device (choke). They were used until 1954. Porsche produced several different engines at this time (1100cc, 1300cc, 1500cc) and the carburetors had various configurations of jetting and venturis dependent on the specific engine. The early 50's body was a 2-piece design with a cold start valve — both used on Normal engines.
In 1954, the 55 model year, Porsche switched to the Solex 32PBIC for Normal engines, and continued use of the 40's for super engines. The PBIC carburetor was close to the PBI in size and appearance, but had a one piece body, no cold start valve, and only one jet/venturi configuration. This body can be used in place of the PBJ with appropriate jetting and addition of the cold start device if PBJ carbs are not available.
The difference between a PBIC and PICB is the cold start valve opening — on the PICB style, a steel plate covers it.
1950–1954 — 40 Single Barrel for Super Engines
Through 1950–54, Porsche used Solex 40 single-barrel carburetors for its 528 Super engines; 40PBIC's and PICB's. They were set up with 2 versions, town and sport, with having a better idle and what we recommend for Concours 356's. Both carburetors had different jetting and venturis depending on the specific engine. These carburetors had the cold start device on the side of the carb.
When Porsche switched to the 616/2 engine they only used the 40PICB's without the cold start device. Jets and emulsion tubes were different from the 528 engines, and used the 29mm venturis as on the earlier sport version.
The 32 and 40 single barrel carbs were in use until 1957. When Porsche switched to the Zenith 32NDIX for Normal and Super engines — Zenith restoration is now handled by Nick Warriner.
Mid 1950s+ — Solex 40PII Sandcast (Carrera)
Throughout this period, Porsche also used Solex dual barrel carburetors in their Carrera engines, designated 40PII. They started with a short (4-bolt) and then a tall (5-bolt) Sandcast aluminum carburetor with different setups pending on type of engine. Later Carrera 2's used the pot metal type bodies with larger jets and venturis as used in the production 356's — they were used on the Carrera 2 type motors.
1959 onward — Solex 40PII-4 (S90 / SC / early 912)
In 1959, for the 1960 model year, Porsche introduced the S90 and once again began using the Solex carburetor. Now it was a dual barrel carburetor with 40mm throats, designated 40PII-4, and had a tall, thin breather tube. With a single shaft across both throats, it remained in use through the S90 series, the 356SC, to the 1967 912. During the transition from S90 to SC, there are at least 4 different variations of the breather tube, until the familiar short fat brass tube we know from the SC and 912 era carburetors. This was a grey pot metal cast carb with silver colored (white) cad plating for the hardware and an aluminum top.
Early Super 90 carbs had a tall, narrow breather tube. There were variations in the breather tubes until the wider, shorter ones used for the SC, until the end of the series. The short fat brass breather tube we see on the later SC's is also the same configuration used on the 912.
Very early Solex had a pot metal top, and that was changed to a cast aluminum top. The Solex was offered as a grey pot metal carb with white cad (silver) hardware. Later, the 912's (1967 model year) appeared with gold cad hardware.
1968 onward — Solex 40PII-4 Split Shaft (emissions)
To deal with the emissions controls being placed on vehicles, starting with the 68 model year, Porsche used the Solex 40PII-4 Split Shaft — a split shaft design with a vacuum distributor for better tuning, improved fuel combustion, and lower emissions. These later carburetors had Gold Cad plating for the hardware, and sometimes a Gold irridite coating on the pot metal cast body. Many owners replaced the vacuum distributor with a stock Bosch .022, and sealed off the vacuum ports on the carburetors. Both styles are in use.
We offer only a solid shaft conversion for the split shaft carburetor. Conversion details are on our Solex page.
As a note, we don't recommend velocity stacks, but they sure look good! Especially on a set of 44mm Solexes!