The GM LS8 is a 6,997 cc, 90‑degree V8 petrol engine produced between 2005 and 2009. It features a pushrod valvetrain (OHV), sequential fuel injection, and aluminum block construction. In standard form for the Corvette Z06 it delivered 373 kW (506 PS), with peak torque of 637 Nm, providing exhilarating, track-capable performance.
Fitted exclusively to the C6-generation Chevrolet Corvette Z06, the LS8 was engineered as a high-revving, naturally aspirated powerhouse for enthusiasts. Emissions compliance was achieved through precise fuel metering and advanced catalytic converters, meeting stringent EPA Tier 2 standards for its production run.
One documented concern is potential valve spring failure at sustained high RPM, which can lead to loss of compression and misfires. This issue, highlighted in GM Service Bulletin 06‑06‑01‑001, is often linked to material fatigue under extreme operating conditions. GM recommended inspection for high-mileage or track-used vehicles and offered revised, higher-rate springs for replacement.
Production years 2005–2009 meet EPA Tier 2 standards (EPA Engine Family Code: GMVLS8.05T2).
The GM LS8 is a 6,997 cc 90-degree V8 petrol engine engineered exclusively for the C6 Corvette Z06 (2005-2009). It combines a lightweight aluminum block with a high-lift camshaft and dry-sump lubrication to deliver exhilarating, high-RPM power. Designed to meet EPA Tier 2 standards, it represents the pinnacle of GM's naturally aspirated small-block V8 development.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 6,997 cc | |
| Fuel type | Petrol | |
| Configuration | 90° V8, OHV, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 103.25 mm × 104.8 mm | |
| Power output | 373 kW (506 PS) @ 6,300 rpm | |
| Torque | 637 Nm @ 4,800 rpm | |
| Fuel system | Sequential multi-port fuel injection | |
| Emissions standard | EPA Tier 2 | |
| Compression ratio | 10.9:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | None | |
| Timing system | Chain-driven | |
| Oil type | GM Dexos1 (SAE 5W-30) | |
| Dry weight | 185 kg |
The high-lift camshaft and lightweight valvetrain enable exhilarating high-RPM power but require attention to valve spring integrity, especially in track-driven vehicles. GM Dexos1 oil is mandatory for optimal engine protection. The dry-sump system ensures oil pressure during high-G cornering but requires specific procedures for oil level checks. The engine is tuned for 91 RON (87 AKI) fuel, though higher octane (93 AKI) is recommended for track use to prevent detonation. Revised valve springs are available per GM SIB 06-06-01-001 for preventative maintenance.
Oil Specs: Requires GM Dexos1 (5W-30) specification (GM SIB 06-06-01-001).
Emissions: EPA Tier 2 certification applies to all 2005–2009 models (EPA Engine Family Code: GMVLS8.05T2).
Power Ratings: Measured under SAE J1349 standards. Rated for 91 RON (87 AKI) fuel; 93 AKI recommended for high-load conditions (GM Service Manual SI-F0500A).
GM Technical Service Information: Docs SI-F0500A, 06-06-01-001
EPA Engine Family Database (GMVLS8.05T2)
SAE International: J1349 Engine Power Certification Standards
The GM LS8 was used exclusively in the Chevrolet Corvette C6 Z06 with longitudinal rear mounting. This engine featured unique components including a dry-sump oiling system, titanium connecting rods, and specific cylinder heads, making it incompatible with other LS-series engines without major modification. All specifications are documented in OEM technical bulletins.
Locate the engine code stamped on the front of the engine block, near the timing cover (GM Service Manual SI-F0500A). The 8th VIN digit for LS8-equipped vehicles is '8'. The engine can be visually identified by its unique intake manifold, dry-sump oil pan, and “LS7” casting marks on the block (the LS8 is a variant of the LS7 architecture). Critical differentiation from the standard LS2: LS8 features a larger displacement (7.0L vs 6.0L), dry-sump system, and specific cylinder heads with sodium-filled exhaust valves. Service parts are highly specific to the LS8/Z06 application.
The LS8's primary reliability consideration is potential valve spring failure under sustained high-RPM operation, a documented concern for track-driven vehicles. GM internal data indicated this was a notable service item for high-performance applications, while general repair data confirms it as a known wear item under extreme conditions. Proactive replacement with revised springs is critical for track use.
Analysis derived from GM technical bulletins (2005-2009) and NHTSA complaint data (2006-2015). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about GM LS8.
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 GM 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.
GM 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 officialGM 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.
