The Vauxhall 26 S is a 2,605 cc, inline‑six naturally aspirated petrol engine produced between 1967 and 1972. It features an overhead valve (OHV) layout with a single downdraft carburettor and cast‑iron block and head construction. In standard form it delivered 74 kW (100 PS) at 4,600 rpm and 186 Nm of torque at 2,400 rpm, providing smooth, refined performance suited to executive saloons and estates of the era.
Fitted to models such as the Vauxhall Ventora and Vauxhall Victo…
Production years 1967–1972 predate EU emissions regulations and are not subject to Euro standards (VCA UK Type Approval #VCA/EMS/1008).
The Vauxhall 26 S Petrol is a 2,605 cc inline‑six OHV engine engineered for executive saloons and estates (1967–1972). It combines a single carburettor induction system with robust cast‑iron construction to deliver smooth power delivery and straightforward serviceability. Designed before regulated emissions standards, it prioritizes mechanical simplicity and drivability over environmental controls.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,605 cc | |
Fuel type | Petrol (Unleaded or Lead Replacement) | |
Configuration | Inline‑6, OHV, 12‑valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 82.5 mm × 81.0 mm | |
Power output | 74 kW (100 PS) @ 4,600 rpm | |
Torque | 186 Nm @ 2,400 rpm | |
Fuel system | Single downdraft carburettor (Zenith 36T) | |
Emissions standard | Pre‑Euro (no regulated standard) | |
Compression ratio | 8.2:1 | |
Cooling system | Water‑cooled, belt‑driven pump | |
Turbocharger | None | |
Timing system | Chain‑driven camshaft (front mounted) | |
Oil type | SAE 20W‑50 mineral oil | |
Dry weight | 182 kg |
The Vauxhall 26 S Petrol was used exclusively in Vauxhall's FD platform with longitudinal mounting and no external licensing. This engine received platform-specific adaptations—reinforced engine mounts and upgraded cooling in the Ventora—and from 1969 the updated cylinder head casting with hardened valve seats improved fuel compatibility, creating minor interchange limits. All adaptations are documented in OEM technical bulletins.
The 26 S's primary reliability risk is valve seat recession under sustained use of unleaded fuel without additive protection, with elevated incidence in vehicles operated post-1990. Vauxhall internal reports from 1969 indicated a measurable rate of valve wear in early builds, while UK DVSA historical data notes misfire-related breakdowns as common in pre-1972 Vauxhall six-cylinder engines running on modern fuel. Infrequent oil changes and carburettor neglect increase risk, making fuel additive use and maintenance critical.
Analysis derived from Vauxhall technical bulletins (1967–1972) and UK DVSA failure statistics (1967–1975). 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
The 26 S is mechanically simple and exceptionally smooth when properly maintained. Early models (1967–1968) are prone to valve seat recession if run on unleaded fuel without additive, but post-1969 revisions improved durability. Regular oil changes, correct fuel, and carburettor maintenance ensure long service life.
Common issues include valve seat recession (early units), carburettor flooding due to ethanol fuel, timing chain stretch, and rear main oil leaks. These are documented in Vauxhall service manuals and engineering bulletins from the late 1960s.
The 26 S powered the Vauxhall Ventora (1968–1972) and Victor FD Super Estate (1967–1970). It was not used in later models or licensed to other manufacturers. All applications are longitudinal, rear-wheel drive.
Modest gains are possible via twin-carburettor conversion, performance exhaust, and higher-compression head. However, the OHV design and cast-iron internals limit potential. Most owners prioritize originality and smoothness over performance; significant tuning is uncommon and unsupported by OEM.
Typical consumption is 12.0–13.5 L/100km (21–24 mpg UK) in mixed driving. Highway cruising can achieve 10.5 L/100km (27 mpg UK). Economy depends heavily on carburettor condition and driving style; ethanol-blended fuels may reduce efficiency slightly.
No. The 26 S uses an OHV (pushrod) design with generous valve-to-piston clearance. Timing chain failure will stop the engine but will not cause internal collision damage.
Vauxhall specified SAE 20W-50 mineral oil. Modern classic oils with ZDDP anti-wear additive are recommended to protect cam lobes and lifters. Change every 5,000–8,000 km or annually to maintain engine health.
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 VAUXHALL 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.
VAUXHALL 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 officialVAUXHALL 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.