Overview
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