GM Performance 12733807 - 6.0L LS Cast Iron Engine Block

The GM Performance 6.0L LS Engine Block (12733807) is a durable, OEM-style cast iron block designed for high-performance builds and reliable factory replacements. Engineered to suit the LS family of cylinder heads, this block is ideal for a wide range of applications including street, performance and motorsport builds.

Featuring a standard 9.240" deck height and a 4.002" cylinder bore as supplied, this block provides a strong and stable foundation for LS-based engines such as LQ4 and LQ9. Its robust cast iron construction offers increased strength and longevity, making it well-suited to high-load and high-horsepower applications.

GM Performance’s LS bare blocks are designed with versatility in mind, supporting multiple LS engine configurations including LS1, LS2, LS3, LS6, LS7, L76 and L92 cylinder heads. Whether you're building a stock replacement or a high-performance engine, this block provides the reliability and engineering expected from GM Performance.

Key Features:

• Genuine GM Performance Block: Designed and manufactured to OEM standards for dependable fitment and performance.
• Cast Iron Construction: Provides superior strength and durability, ideal for performance and heavy-duty applications.
• LS Compatibility: Suits a wide range of LS cylinder heads including LS1, LS2, LS3, LS6, LS7, LQ4, LQ9, L76 and L92.
• Standard Deck Height: 9.240" deck height ensures compatibility with standard LS rotating assemblies.
• 6-Bolt Main Caps: Enhances bottom-end strength and stability under high load conditions.
• Performance Ready: Suitable for stock rebuilds through to high-performance engine builds.

Technical Specifications: