6.6L V-8 L8T


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Horsepower:  401 hp (299kW) @5200 RPM*
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Torque:  464 lb-ft (629Nm) @4000 RPM*
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Fuel Type:  Regular Gasoline (87 Octane)

6.6L V-8 L8T Features
& Specifications

The L8T is meant for grunt work, thanks to an impressive 464 lb-ft. of peak torque that arrives 200 rpm sooner (and is 22 percent more) than GM’s previous 6.0L V-8 HD gasoline engines. Direct injection technology provides precise fuel control and enables a higher compression ratio that broadens the torque curve and contributes to a power output of 401 hp. This broad torque band provides a stronger feeling of on-demand power at all speeds.

type: 6.6L V-8
displacement: 6564 cc (400 CI)
engine orientation: Longitudinal
compression ratio: 10.8:1
valve configuration: Overhead Valves
valves per cylinder: Two
assembly site: Tonawanda, NY
valve lifters: Hydraulic Roller
firing order: 1 - 8 - 7 - 2 - 6 - 5 - 4 - 3
bore x stroke: 103.25 x 98.0 mm
fuel type: Regular Gasoline (87 Octane)
horsepower: 401 hp (299kW) @5200 RPM*
torque: 464 lb-ft (629Nm) @4000 RPM*
maximum engine speed: 5600 RPM
emissions control: Catalytic Converter, Three-way catalyst, Positive Crankcase Ventilation
block: Cast Iron
cylinder head: Cast Aluminum
intake manifold: Composite
exhaust manifold: Stainless Steel
main bearing caps material: Cast Nodular
crankshaft: Forged Steel
camshaft: Billet Steel
connecting rod: Forged Powder Metal
*As tested in Chevrolet Silverado Heavy-Duty