Overview Brand: ATK High Performance Engines Manufacturer’s Part Number: HP97 Part Type: Crate Engines Product Line: ATK High Performance Chevy LM7 5.3L 385 HP Long BLock Crate Engines Summit Racing Part Number: HPE-HP97 UPC: 00653517137211 Crate Engine Family: Chevy LS Actual Engine Displacement: 5.3L/325 Crate Engine Cylinder Head Material: Aluminum Engine Block Material: Cast iron Advertised Compression Ratio: 9.5:1 Assembled: Yes Engine Balance: Internal Cam Style: Hydraulic roller, OE roller Rear Main Seal Style: 1-piece Intake Manifold Included: No Cylinder Heads Included: Yes Carburetor Included: No Throttle Body Included: No Distributor Included: No Oil Pan Included: No Valve Covers Included: No Timing Cover Included: No Water Pump Included: No Harmonic Balancer Included: No Flexplate Included: No Flywheel Included: No Air Cleaner Included: No Spark Plugs Included: No Spark Plug Wires Included: No Computer Included: No Wiring Harness Included: No Supercharger Included: No Remanufactured: Yes Quantity: Sold individually. Notes: Custom chassis dyno tune required. Headers and upgraded injectors recommended for optimal performance. 24 tooth reluctor wheel. ATK High Performance Chevy LM7 5.3L 385 HP Long BLock Crate Engines With ATK High Performance Chevy LM7 5.3L 385 hp long block crate engines expect big mid to upper end power and a noticeable idle. They were designed to be performance upgrades for a 1999-2007 Chevy truck LM7 or an LS swap in a hot rod. Technical specifications include: * Horsepower: 385 * Torque: 390 * Block: GM 5.3L iron LM7 * Bore/stroke: Up to 3.809 x 3.622 * Year range: 1999-2007 * Displacement: 323 c.i.d. * Crankshaft: OEM GM 3.622 in. stroke internally balanced 24 tooth reluctor wheel .857 in. flange * Connecting rods: OE GM forged powder metal 6.093 in. stock bolts * Pistons: Hypereutectic dish * Piston rings: Moly rings * Compression ratio: 9.5:1 compression * Camshaft: Hydraulic roller * Camshaft specifications: Custom grind * Camshaft bearings: Installed and clocked to OEM position * Cylinder heads: OE aluminum 61.15cc 1.89/1.55 * Freeze plugs: Brass installed and sealed * Rocker arms: OE powdered metal 1.7 ratio * Oil Galley plugs: Installed and sealed * Weight: 385