ATK High Performance GM 350 390 HP Stage 1 Long Block Crate Engines HP89

Buy GM 350 390 HP Stage 1 Long Block Crate Engines HP89 Online

The ATK High Performance GM 350 390 HP Stage 1 Long Block Crate Engine HP89 is designed for classic Chevrolet performance projects, including street rods, muscle cars, and trucks. This 350 cubic-inch (5.7L) Chevy small-block combines a remanufactured 4-bolt main block with performance-focused components for a strong and dependable engine package.

The HP89 produces a listed 390 horsepower and features performance aluminum cylinder heads, a hydraulic roller camshaft, hypereutectic pistons, and an OE crankshaft and connecting rods. The engine uses a 1-piece rear main seal and is mercury 8 hp outboard motor assembled and balanced for 350cc hp consistent performance. Its listed compression ratio is 9.5:1, making it suitable for pump-gas-oriented applications.

This Stage 1 long block includes cylinder heads, valve covers, timing cover and timing set, plus an oil pan, oil pump, and pickup tube. Components such as the intake manifold, carburetor, distributor, water pump, harmonic balancer, flywheel, and wiring atk 350 crate engine harness are not included, allowing builders to select supporting components according to their project requirements.

With its familiar small-block Chevy architecture and 390 HP output, the ATK HP89 provides a practical foundation for upgrading or restoring compatible performance vehicles.

Product Specifications

• Brand: ATK High Performance Engines
• Part Number: HP89
• Engine Type: Chevrolet Small Block V8
• Displacement: 350 cu. in. / 5.7L
• Horsepower: 390 HP
• Torque: 420 ft-lb
• Block: 4-bolt main GM crate block
• Block Material: Cast iron
• Cylinder Heads: ATK High Performance aluminum
• Camshaft: Hydraulic roller
• Compression Ratio: 10.0:1
• Rear Main Seal: 1-piece
• Crankshaft: OE crankshaft
• Pistons: Hypereutectic
• Valve Size: 2.020 in. intake / 1.600 in. exhaust
• Rocker Arms: 1.6:1 steel
• Bore/Stroke: 4.040 in. × 3.480 in.
• Assembly: Assembled and balanced
• Oil Pan: Included
• Oil Pump & Pickup Tube: Included
• Valve Covers: Included
• Timing Cover & Timing Set: Included
• Intake Manifold: Not included
• Carburetor: Not included
• Distributor: Not included
• Water Pump: Not included
• Harmonic Balancer: Not included
• Flywheel/Flexplate: Not included
• Wiring Harness/Computer: Not included
• Fuel Recommendation: 91-octane pump gas according to the detailed ATK specifications.

Product Benefits

• 390 HP Performance: Provides a substantial performance-oriented output from a traditional 350ci small-block platform.
• Strong Torque Output: The engine is listed at up to 420 ft-lb of torque, supporting responsive performance.
• Aluminum Cylinder Heads: Performance aluminum heads help create a performance-focused cylinder-head configuration.
• Hydraulic Roller Camshaft: Designed as part of the engine’s performance-oriented valvetrain package.
• 4-Bolt Main Block: Provides a robust foundation for performance applications.
• Ready-Assembled Package: The engine arrives assembled, reducing the need to build the long block from individual components.
• Classic Chevy Platform: The 350 small-block architecture is suitable for a range of compatible Chevrolet performance and restoration projects.
• Flexible Component Selection: Because major external components such as the intake manifold, carburetor, and distributor are not included, builders can select supporting components appropriate to their project.

How much power does the ATK HP89 produce?

The product page lists the ATK HP89 at 390 horsepower and identifies it as a 350ci/5.7L Chevy small-block Stage 1 long-block crate engine.

What components are included with the HP89?

The package includes performance aluminum cylinder heads, valve covers, timing cover and timing set, oil pan, oil pump, and pickup tube. The intake manifold, carburetor, distributor, water pump, and several other accessories are not included.