The Porsche 901.08 is a 2,195 cc, flat‑six (horizontally opposed) naturally aspirated petrol engine produced between 1966 and 1967. It powered the Porsche 911S, delivering enhanced performance over earlier units through higher compression and revised valve timing. Featuring an air‑cooled design, dual overhead camshafts (DOHC), and Bosch mechanical fuel injection, it generated 160 PS (118 kW) at 6,600 rpm and 186 Nm of torque. This engine marked Porsche's first use o…
The 901.08 predates EU emissions regulations and was not type-approved under modern frameworks (VCA/EU).
The Porsche 901.08 is a 2,195 cc flat‑six air‑cooled petrol engine engineered for performance coupés (1966–1967). It combines DOHC valvetrain architecture with Bosch mechanical fuel injection to deliver high-revving character and motorsport-derived responsiveness. Designed before emissions regulation, it prioritizes mechanical precision and power density.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,195 cc | |
Fuel type | Petrol (Gasoline) | |
Configuration | Flat‑6 (horizontally opposed), DOHC, 12‑valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 84.0 mm × 66.0 mm | |
Power output | 118 kW (160 PS) @ 6,600 rpm | |
Torque | 186 Nm @ 5,200 rpm | |
Fuel system | Bosch mechanical fuel injection (PI system) | |
Emissions standard | Not applicable (pre-regulation era) | |
Compression ratio | 9.8:1 | |
Cooling system | Air‑cooled (fan‑driven) | |
Turbocharger | None | |
Timing system | Gear-driven dual overhead camshafts | |
Oil type | SAE 20W-50 mineral oil (API SC/SD) | |
Dry weight | 182 kg |
The Porsche 901.08 was used exclusively in the Porsche 911S with rear‑engine, longitudinal mounting. This high‑performance variant was developed for homologation and motorsport support, featuring unique cylinder heads, camshafts, and injection calibration. No cross‑manufacturer or platform sharing occurred. All revisions are documented in Porsche engineering bulletins.
Engine Finders UK Ltd, which operates EngineCode.uk, can pass your enquiry to engine suppliers in the UK. The service is for vehicles in the United Kingdom, with UK delivery or fitting. This is a commercially connected service, and sending an enquiry does not confirm diagnosis or compatibility.
Diagnostic reminder: If a technician has recommended replacing the engine, you can send an enquiry to engine suppliers in the UK. Confirm the diagnosis first: an engine-code record does not diagnose a fault.
The 901.08's primary reliability challenges are valve train wear under improper clearance settings and fuel system sensitivity to calibration drift. Porsche’s 1967 durability logs noted excellent high-RPM stability when maintained per specification, but modern operation without period-correct fuel or service intervals increases cam and lifter degradation. Cold-engine stress remains a key concern for longevity.
Analysis derived from Porsche technical bulletins (1966–1968) and EU historical vehicle documentation (2010–2023). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
With strict adherence to maintenance and period-correct fluids, the 901.08 is robust and high-revving. Its DOHC design rewards precision care but suffers from cam wear if valve clearances or oil specs are neglected. Restored units with hardened valve seats and correct mineral oil can deliver decades of reliable performance.
Top issues include cam lobe wear from improper valve clearance, Bosch PI injection calibration drift, oil leaks from aged gaskets, and ignition timing instability due to distributor wear. All are well-documented in the 1966 Porsche 911S Workshop Manual.
Exclusively the 1966–1967 Porsche 911S (Type 901/08). Approximately 2,200 units were produced for road use, primarily to satisfy FIA homologation for Group 3 racing. No other models or manufacturers used this engine.
Yes. Common upgrades include 10.5:1 pistons, race camshafts, and modified injection, yielding ~180 PS. The DOHC bottom end is strong, but exceeding 190 PS requires reinforced connecting rods. Period-correct aesthetics are often preserved for historic racing eligibility.
Typical consumption is ~13.0 L/100km (city) and ~9.0 L/100km (highway), or about 22–26 mpg UK combined. Fuel economy is secondary to performance; aggressive driving can drop efficiency below 20 mpg UK.
No. Like all early air-cooled flat-six Porsche engines, the 901.08 is non-interference. Valve-to-piston contact will not occur if timing components fail, though valve float can still cause mechanical damage at high RPM.
Porsche specified SAE 20W-50 mineral oil meeting API SC/SD with high ZDDP (>1200 ppm) to protect flat-tappet cams. Modern synthetics are discouraged unless the engine is rebuilt with upgraded valvetrain components.
Comprehensive technical documentation and regulatory references
EngineCode.uk is operated by Engine Finders UK Ltd. It provides engine-reference information and an optional commercial enquiry service. It is not an official manufacturer website. Check the record's sources and confirm vehicle-specific details before relying on it for parts, repairs or replacement.
Our editorial standard prioritises relevant manufacturer documentation and official regulatory sources. The sources and verification status for a record should be checked alongside the data.
A statement is not verified merely because a source is listed. Where supporting evidence is missing or conflicting, the record should identify that limitation. Please report unsupported or inconsistent information.
Transparency in gaps
A missing or unverified value does not mean the manufacturer has withheld it. We distinguish information not yet verified, information not available to us, and information explicitly not disclosed by the source.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Records are subject to review and correction. Source links, dates and verification notes should be read with the technical information. Our Editorial and Sourcing Policy explains our standards and review process.
Found an error or missing source? Report a problem with this page. Include the field or statement concerned and a supporting source if available. You can also email corrections@enginecode.uk.
Copyright and permissions
Images and other material may be protected by copyright. Attribution does not by itself grant permission to reuse material. If you believe material on this site infringes your rights, contact copyrights@enginecode.uk with the page URL and details of your claim. We will review the material and take appropriate action.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
Our Privacy Policy explains how Engine Finders UK Ltd uses information from visits, vehicle lookups, enquiries and messages. Our Cookie Policy explains cookies and similar technologies and how to change your choices.
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
Ownership and commercial services
EngineCode.uk is owned and operated by Engine Finders UK Ltd. Alongside our reference content, we offer an optional replacement-engine enquiry service through Engine Finders and may identify relevant services provided by businesses connected with us. These commercial connections are disclosed. Using an enquiry service is not required to read our reference content.
Engine Finders UK Ltd operates this website. Our optional enquiry service has a commercial purpose. Our Ownership and Commercial Disclosure explains the relationship between the reference website and that service. Participating suppliers pay a fee or subscription to participate on the network and receive quote requests.
Use this record as a starting point for identification. Specifications and vehicle applications may contain errors or omissions. Confirm the exact engine variant and compatibility using vehicle-specific documentation and a qualified supplier or technician.
All external links open in new tabs. Please verify current availability of resources.