Looking for big LS engine power at an affordable price? This remanufactured 5.3L LS long block crate engine is rated at 450 HP and 420 lbs.-ft. torque! This engine will give you the performance and drivability you have been searching for at a price you can afford. You will save time and money by leaving the machine-work and assembly to us. Just bolt on your accessories and drop it in. These engines are machined and assembled for us by the guys at ATK, and backed with a 2-year unlimited mile warranty for peace of mind. This engine comes exactly as pictured, so you will need to source all hardware, seals, covers not pictured, etc.

Technical specifications:

* Horsepower: 450+
* Torque: 420+
* Block: Seasoned OE LM7/5.3L iron
* Bore/stroke: 3.800-3.820 in. x 3.622 in.
* Year range: 1999-2007
* Displacement: 323 C.I.D.
* Crankshaft: OEM GM 3.622 in. stroke internally balanced 24x-tooth reluctor wheel
* Connecting Rods: OE GM forged powder metal 6.093 in.
* Pistons: Hypereutectic flat top
* Piston rings: Moly
* Compression ratio: 10:1 compression
* Camshaft: Summit Racing Pro LS Roller
* Camshaft specifications: Lift- 550/550, Duration @.050- 222/232
* Camshaft bearings: Installed and clocked to OEM position
* Cylinder heads: #799 or #243 OE aluminum 64cc 2.00 in./1.55 in. valves [Cathedral port]
* Freeze plugs: Brass installed and sealed
* Rocker arms: OE powdered metal 1.7 ratio
* Oil Galley plugs: Installed and sealed

Note to buyers : As of 05.17.2024 we are able to offer free freight shipping on this item, however this may not last forever, so there is a chance you will be billed for freight shipping charges