The Volkswagen AB is a 1,582 cc, air‑cooled flat‑four petrol engine produced between 1970 and 1973. It featured a single overhead camshaft (SOHC) per cylinder bank and a single downdraft carburettor, delivering a modest power output suitable for its era. The horizontally opposed layout provided a low centre of gravity, contributing to the vehicle's characteristic handling stability.
Fitted primarily to the Volkswagen Type 4 (411/412) and early Porsche 914 models, the AB engine was engineered for reliable, economical transportation with an emphasis on simplicity and ease of maintenance. Emissions control was minimal for the period, typically relying on basic crankcase ventilation (CCV), with compliance generally falling under pre‑Euro regulatory frameworks.
One documented service concern involves premature wear of the camshaft lobes and hydraulic lifters, a condition noted in Volkswagen Service Bulletin 01‑72‑03. This issue was often attributed to marginal oil flow or the use of incorrect oil viscosity under sustained high‑load conditions. The design was superseded by the more robust AC variant, which incorporated revised camshaft metallurgy and improved oiling passages.
Volkswagen
Production years 1970–1973 predate formal Euro emissions standards; compliance was governed by national regulations of the era (VCA UK Type Approval historical records).
The Volkswagen AB is a 1,582 cc air-cooled flat-four petrol engine engineered for mid-size sedans and coupes (1970-1973). It combines a simple SOHC valvetrain with a single carburettor to deliver smooth, linear power delivery and straightforward mechanical character. Designed for an era before stringent emissions controls, it prioritises mechanical simplicity and serviceability.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,582 cc | |
| Fuel type | Petrol | |
| Configuration | Flat-4, SOHC, 8-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 85.5 mm × 69.0 mm | |
| Power output | 59 kW (80 PS) @ 4,300 rpm | |
| Torque | 128 Nm @ 2,600 rpm | |
| Fuel system | Single 32 PDSIT downdraft carburettor | |
| Emissions standard | Pre-Euro (National Regulations) | |
| Compression ratio | 7.7:1 | |
| Cooling system | Air-cooled (fan-forced) | |
| Turbocharger | None | |
| Timing system | Gear-driven camshafts | |
| Oil type | SAE 20W-50 (mineral) | |
| Dry weight | 108 kg |
The air-cooled design offers mechanical simplicity but demands vigilant monitoring of oil temperature and level, especially under load or in hot climates. Using the specified SAE 20W-50 mineral oil is critical to ensure adequate film strength for the flat-tappet camshaft and hydraulic lifters. Regular valve clearance adjustments (every 10,000 km) are mandatory for optimal performance and noise control. The single carburettor requires periodic synchronization and cleaning to prevent lean running conditions. Pre-1972 units are particularly susceptible to camshaft wear; inspection per Volkswagen SIB 01-72-03 is advised during major services.
Oil Specs: Requires SAE 20W-50 mineral oil specification (Volkswagen Workshop Manual M-411). Modern synthetic oils may not be suitable without expert consultation.
Emissions: Pre-Euro certification; governed by national vehicle regulations of the 1970-1973 period (VCA Historical Records).
Power Ratings: Measured under DIN 70020 standards. Output is gross rating (Volkswagen Group PT-1972).
Volkswagen Technical Information System: Workshop Manual M-411, SIB 01-72-03
Volkswagen ETKA Parts Catalogue (Doc. 001.582.AB)
DIN Standard 70020: Engine Power Measurement
The Volkswagen AB was used across Volkswagen's Type 4 platform with rear longitudinal mounting. This engine received platform-specific adaptations-slightly different engine tinware and exhaust routing for the Porsche 914-creating minor interchange considerations. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped on the crankcase, just below the generator/alternator stand (Volkswagen Workshop Manual M-411). The code "AB" is typically followed by a sequential serial number. Visual identification: Features a single, centrally mounted 32 PDSIT carburettor and a distinctive air-cooling shroud. Critical differentiation from the later AC engine: AB engines have a lower 7.7:1 compression ratio and are more prone to camshaft wear as per SIB 01-72-03. Engine tinware (cooling shrouds) from Type 4 and 914 applications are not always directly interchangeable due to mounting flange differences.
The AB's primary reliability risk is camshaft and lifter wear, with elevated incidence in engines subjected to sustained high speeds or inadequate oil maintenance. Volkswagen internal service data from the early 1970s indicated a notable number of premature cam failures, while owner club surveys frequently cite oil-related issues. Infrequent oil changes and the use of incorrect viscosity make adherence to the SAE 20W-50 specification critical.
Analysis derived from Volkswagen technical bulletins (1970-1975) and aggregated owner club maintenance data (1970-2023). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about VOLKSWAGEN AB.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with VOLKSWAGEN or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
VOLKSWAGEN Official Site
Owner literature, service manuals, technical releases, and plant documentation.
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.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
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.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialVOLKSWAGEN documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed“ .
All external links open in new tabs. Please verify current availability of resources.
