ATK High-Performance GM 408 LQ4 Stroker — Stage 1 long-block crate engine producing about 600 hp. Built from the LQ4 platform and stroked to 408ci, it’s supplied as a long-block for LS swaps and performance installations.

• GM LQ4-based 6.0L block stroked to 408ci
• Approximately 600 horsepower — Stage 1 performance rating
• Long-block configuration (assembled short block + cylinder heads) — final accessories required for installation
• Designed for LS swaps, muscle cars and performance projects
• Optimized for strong torque and mid-range power delivery
• Manufacturer fitment/spec and installation support available