Continuing the tradition of great small-block V-8 engines, the 5.3L LS engine has been one of the most popular GM has ever built. It's been installed in millions of GM-built pickups, work trucks, vans, and SUVs. But, leave it to the GM Performance Parts engineers to go one step further and upgrade the 5.3L LS. The result is a High Output 5.3 that is just as capable serving as a workhorse-it's just a little bit more fun.
Based on the tough, proven, and dependable 5.3L engine, it's the same long-lived production engine that you'll find in our award winning full-sized truck and SUV line. The stock 5.3 offers a dependable 295 horsepower and 325 lb.-ft. of torque from the 96mm bore by 92mm stroke engine design.
What makes the 5.3 High Output crate engine so special is that the GM engineers have added a GM Performance Parts custom cam and Grafal-coated pistons. With these simple upgrades, the 5.3 HO kicks out 332 horsepower and 352 lb.-ft. of torque. And, just like the stock 5.3, the 5.3 HO is capable of thousands of miles of dependable service while returning outstanding fuel mileage, thanks to the superior design of the LS Family of engines.
Displacement: 327
Horsepower: 327 @ 5500 Rpm
Torque: 347 @ 4600 Rpm
Bore & Stroke: 3.75" x 3.62"
Engine Block: Cast Iron with 6-Bolt cross-drilled iron main caps
Crankshaft: Nodular Iron
Connecting Rods: Powdered metal steel
Pistons: Hypereutectic aluminum
Camshaft: Hydraulic Roller
Camshaft Lift: .467 Intake / .479 Exhaust
Camshaft Duration @ .050: 196° Intake / 201° Exhaust
Cylinder Heads: Aluminum; Cathedral Port
Valve Size: 1.89 Intake / 1.55 Exhaust
Compression Ratio: 9.5:1
Rocker Arms: Investment cast , Roller Trunnion
Rocker Arm Ratio: 1.7:1
Recommended Fuel: 87 Octane
Maximum Rpm: 6000
Balance: Internal