1975 Porsche Turbo Part Number Guide: Identifying OEM Components

The 1975 Porsche Turbo (internal code 930) is a landmark car. It was the first production turbocharged Porsche and remains a coveted collector vehicle. Whether you are restoring a barn find, rebuilding a track car, or simply maintaining a weekend driver, knowing the correct OEM part numbers is essential. Porsche parts for this era use a specific numbering system, and many components are no longer available from the factory. This guide explains how to find, verify, and cross-reference part numbers for a 1975 930.

Why Part Numbers Matter for a 1975 Porsche Turbo

Using the correct part number ensures proper fit, function, and originality. A 1975 Turbo is not the same as a later 930 or a naturally aspirated 911. Porsche engineers changed parts frequently during production. For example, early 1975 cars used a different turbocharger (K27-7200) than later models. The wrong part can affect performance, safety, or resale value. Originality also matters for concours judging or insurance valuation. A mismatched part number can indicate a non-original car.

How to Locate Part Numbers

On the Car Itself

Many parts have stamped or cast numbers. Engine case halves, cylinder heads, transmission cases, and brake calipers all show their part numbers. Look for letters and numbers like 930.XXX.XXX.XX. For body parts, check the underside of fenders, hoods, and doors. Interior components often have stickers or molded numbers on the backside. Clean the area with a solvent to read faint stamps.

Factory Parts Catalogs and Microfiche

Porsche issued paper parts catalogs (called PET – Porsche Electronic Parts Catalog) for each model year. The 1975 Turbo is covered in PET number WKD 911 020 75. You can find scanned versions online from Porsche clubs or specialist vendors. These catalogs list every part with its number, description, and quantity. They also show supersessions – when a part was replaced by a newer number. A microfiche reader is not required; digital PDFs are widely available.

Online Databases and VIN Decoding

Websites like Pelican Parts, Stoddard, and Sierra Madre Collection offer lookup tools. Enter your VIN (begins with 930670xxxx) to see the original build sheet. This sheet lists major part numbers for engine, transmission, and options. However, online databases may not cover every minor component. Cross-reference with factory catalogs for accuracy.

Common Parts and Their Numbers

Engine Components

The 1975 930 engine (type 930/50) uses unique parts. Key numbers:

• Turbocharger: 930.123.015.00 (K27-7200). Replaced by 930.123.015.01.
• Intercooler: The 1975 model has no intercooler; it uses a water-cooled charge air system. Part number for the charge air cooler: 930.110.131.00.
• Crankcase: 930.101.101.02.
• Cylinder head (left): 930.104.022.02; (right): 930.104.023.02.
• Fuel injection: Bosch K-Jetronic. Airflow sensor plate part: 930.606.102.00.

Transmission and Drivetrain

The 930 uses a 4-speed manual (Type 930/30). Ratios are different from later 5-speeds.

• Transmission case: 930.301.011.02.
• Differential side gears: 930.332.113.00.
• Clutch disc: 930.116.012.00 (240mm).
• Half shafts (axles): Left: 930.332.031.01; Right: 930.332.032.01.

Body and Trim

Early 930s have specific sheet metal for the wider rear fenders. Many parts are shared with the 1975 911 Carrera but have separate part numbers.

• Rear fender (left): 930.503.043.00.
• Front bumper impact strip: 930.505.921.00.
• Rear bumper valance: 930.505.421.00.
• Whale tail spoiler (rubber lip): 930.512.231.00.

Interior and Electrical

The 1975 interior uses early style gauges and switches.

• Instrument cluster (VDO): 930.641.101.00.
• Turbo boost gauge: 930.641.281.00.
• Starter motor: 930.604.101.00 (Bosch 0.001.208.022).
• Ignition distributor: 930.602.101.00.

Dealing with Discontinued Parts (NLA)

Porsche discontinued many 1975-specific parts. When a part is no longer available (NLA), you have options:

• Reproduction parts: Specialists like Porsche Classic, Stoddard, and various European manufacturers produce high-quality replicas. For example, the whale tail rubber lip is reproduced by multiple vendors. Always ask if the reproduction matches the original part number and material.
• Used original parts: Check forums (Pelican, Rennlist), swap meets, or dismantlers like Parts Heaven or DC Automotive. Verify the part number before buying.
• Supersession: Porsche often replaced old part numbers with new ones that fit multiple years. For instance, the original turbocharger (930.123.015.00) supersedes to 930.123.015.01, which is still available. Use a PET catalog to check supersessions. Note that some supersessions may change the part slightly (e.g., updated material).

Reproduction and OEM Alternatives

Some parts are made by original suppliers under their own brand. Bosch, Hella, Sachs, and others produce components without the Porsche crest. These may be identical to the original but sold under a different number. For example, the Bosch starter can be sourced as a Bosch reman unit. This is often cheaper than a Porsche-bagged part.

Using Supersession Numbers

Always check if a part number has been superseded. Porsche releases updates for reliability or emissions. A supersession does not always mean the part fits perfectly – sometimes mounting points change. Verify with a specialist if you are unsure. The PET catalog lists effective date ranges. For a 1975 car, many supersessions occurred in the early 1980s.

Final Recommendation

To locate the correct 1975 Porsche Turbo part number, start with the factory PET catalog. Download the PDF specifically for the 930/1975 model year. Cross-reference any number you find on the car with the catalog. If you need to buy a part, contact a dedicated Porsche classic parts supplier. Tell them the exact part number and your VIN. For NLA items, consider quality reproductions from reputable vendors. Avoid generic aftermarket parts without proven fit – they can compromise the car's value and safety. Keep a binder with printed catalog pages and notes for your car's specific numbers. This saves time and money in the long run.

Restoring a 1975 Turbo is a rewarding project. Getting the part numbers right keeps the car authentic and reliable. Use this guide as a starting point, and always double-check before buying. The Porsche community is generous with knowledge; don't hesitate to ask in forums or clubs. With patience and the right numbers, your 930 can stay on the road for another fifty years.