0450905021 (also written as 0 450 905 021) is the exact full Bosch 10-digit manufacturer part number for the classic Bosch 71020 fuel filter. It is also known alternatively by the short catalog number F5021. This high-pressure, metal-canister fuel filter is engineered for vintage European continuous injection systems (such as Bosch K-Jetronic / CIS) .
Technical Specifications
- Micron Rating: 12 Micron Nominal
- Filter Media: Cellulose
- Body Dimensions: 134 mm Length × 55.5 mm Diameter
- Inlet Port Fitting: M14 × 1.5 metric female thread
- Outlet Port Fitting: M12 × 1.5 metric female thread
This exact filter is utilized across a wide variety of classic European platforms from the late 1970s through the early 1990s:
- Porsche: 911 (1970s/80s variants) and 924 (Porsche OEM Part Number:
93011019600)
- Volkswagen: Mk1 and Mk2 8v CIS-injected vehicles (Golf, Jetta, Rabbit, Scirocco) (VW OEM Part Number:
431133511)
- Volvo: 240, 740, and 940 series turbo/non-turbo models (Volvo OEM Part Number:
1276050 or 1266229)
- Audi: Classic 4000, 5000, and Coupe models (Audi part numbers 431133511 and 431133511A)
- Saab: 900 variants
Porsche - This filter corresponds exactly to Porsche factory part number 930-110-196-00. It is engineered specifically for early Continuous Injection System (CIS / K-Jetronic) classic models, cutting off around the 1980/1981 model year split when Porsche transitioned fuel system line configurations. This filter serves a very narrow, specific era of classic air-cooled and transaxle models. If you're displaying an older 911 for concour and need a "period filter" in keeping the car original, these are NOS from 20+ years ago.
Porsche 911 (1973.5–1980)
- 1973.5 911 T: Fits late 1973 2.4L models exclusively factory-equipped with the mid-year CIS injection update. It does not fit early 1973 carbureted or Mechanical Fuel Injection (MFI) cars.
- 1974–1977 911 Base & 911 S: Fits all standard 2.7L CIS-injected iterations.
- 1978–1980 911 SC: Fits early 3.0L Super Carrera platforms. Note that it also serves as the direct factory supersession for the discontinued early SC filter ending in 076 00 (Bosch 0450905079).
Porsche 924 (1977–1980)
- 1977–1980 924 Base: Fits the early naturally aspirated 2.0L 4-cylinder transaxle platforms utilizing the primitive K-Jetronic fuel distribution block.
