ATK GM 383 Stroker HP90 Marine Grade Stage 1 Engine

ATK HP90 Marine Grade Performance Engine

ATK GM 383 Stroker HP90 Marine Grade Stage 1 Engine units deliver a specialized high-torque marine powertrain solution designed for superior reliability in demanding aquatic environments. This 6.3L 383ci stroker features cast-iron cylinder heads and a seasoned cast-iron block, engineered to provide the high low-end torque required for marine propulsion and heavy-duty boating. Built with marine-specific standards, this Small Block Chevy architecture is a professional-grade fit for inboard marine applications requiring a robust and durable engine foundation.

As a Stage 1 remanufactured long block foundation, the ATK HP90 arrives with an oil pan and is designed to accommodate marine-grade accessories and cooling systems provided by the builder. The internal assembly is precision-balanced to ensure smooth operation under sustained loads, while the seasoned block provides the structural integrity necessary for high-duty cycles. Protected by a 1-Year limited warranty, this marine stroker is the ideal choice for enthusiasts and professionals demanding displacement-heavy performance and long-term durability on the water.

Key Features of ATK High Performance HP90

• 6.3L 383ci stroker displacement optimized for marine torque.
• Cast iron cylinder heads and block for traditional structural strength.
• Engineered for high-duty cycles and sustained marine loads.
• Internal and external engine balance ensures vibration-free operation.
• Professional-grade assembly meets marine reliability standards.
• Seasoned block casting provides long-term structural integrity.
• Backed by a professional 1-Year limited warranty.

HP90 Include:

• Oil Pan