ATK Ford 408 Stroker 480 HP HP81M Stage 2 Mid-Dress Engine

ATK HP81C 408 Stroker 480 HP Elite Performance Build

The ATK HP81C 480 HP Stage 3 assembly is a high-output 6.7L Ford Windsor powerhouse engineered for maximum street/strip performance. Utilizing a rugged cast iron block and high-flow aluminum cylinder heads, this precision-machined stroker achieves a formidable 480 HP output while maintaining superior thermal efficiency. Every component is balanced internally to provide the high-RPM stability and visceral power required for professional-grade American performance builds.

Perfect for vintage muscle car conversions and performance-oriented street projects, this Ford 408 Stroker 480 HP assembly provides a comprehensive turn-key solution. As an internally balanced Windsor power plant, it includes a factory-matched harmonic balancer and flexplate to ensure seamless rotational harmonics. This Stage 3 configuration comes fully equipped with a carbureted induction system and electronic ignition, requiring only premium high-octane fuel to support its advanced aluminum head architecture.

Comprehensive Engineering Metrics: HP81C Series

• Massive 6.7L 408 Stroker displacement offers a formidable torque foundation for competition.
• High-flow aluminum cylinder heads significantly enhance engine cooling and airflow capacity.
• Modern hydraulic roller camshaft architecture delivers aggressive and stable valve timing.
• Rugged cast iron block construction ensures maximum structural integrity under high-stress loads.
• Internal rotational balance provides remarkably smooth operation across the entire powerband.
• Advanced one-piece rear main seal design prevents traditional Windsor oil leak issues.
• Complete Stage 3 induction features a performance carbureted intake manifold and matched carburetor.
• Integrated ignition package includes a precision distributor, spark plugs, and high-performance wires.
• Pre-installed water pump and harmonic balancer significantly reduce total installation time.
• Comprehensive one-year warranty coverage provides essential protection for your performance investment.

Testing this ATK HP81C 408 Stroker revealed a brutal mid-range pull and immediate throttle response. The aluminum heads effectively manage heat during sustained operation, while the internal balance provides a refined feel despite the 480 HP output. It delivers an aggressive, visceral Windsor grunt, serving as a premier turn-key choice for elite automotive projects.

Hardware Included with HP81C Complete Package

• Precision Assembled Engine Block and Aluminum Heads
• Carbureted Intake Manifold and Matched Carburetor
• Electronic Distributor, Spark Plugs, and Ignition Wires
• Water Pump, Harmonic Balancer, and Flexplate
• Performance Oil Pan, Valve Covers, and Timing Cover