ATK GM 383 TBI Stroker 320 HP HP05 Stage 1 Long Block

ATK HP05 320 HP TBI Stroker

ATK GM 383 TBI Stroker 320 HP HP05 Stage 1 Long Block engines offer a high-torque remanufactured long block solution designed for TBI-equipped classic trucks and daily drivers. This 6.3L 383ci build utilizes cast-iron cylinder heads and a seasoned cast-iron block to deliver a verified 320 horsepower. Engineered with a hydraulic roller camshaft, this Small Block Chevy architecture is a direct performance fit for GM C/K trucks and SUVs requiring the increased displacement and low-end torque of a stroker while maintaining TBI compatibility.

Integrating this high-torque engine foundation requires builders to provide their own TBI induction and ignition components, as the unit arrives in a Stage 1 un-dressed state. The ATK HP05 includes a factory-installed oil pan and is protected by a professional 1-Year limited warranty to ensure long-term structural reliability. Featuring a modern one-piece rear main seal to prevent fluid weeping, this 383 TBI stroker is the ultimate choice for enthusiasts demanding classic torque and professional assembly standards in a traditional GM chassis project.

Key Features of ATK High Performance HP05

• 6.3L 383ci stroker displacement delivering 320 horsepower performance.
• Cast iron cylinder heads and block for traditional durability.
• Hydraulic roller camshaft ensures stable valvetrain operation.
• Optimized for TBI-equipped GM truck and SUV platforms.
• One-piece rear main seal prevents chronic small-block oil leaks.
• Seasoned cast-iron block foundation for superior strength.
• Protected by a 1-Year professional limited warranty.

HP05 Include:

• Oil Pan