Chevrolet Performance 19433748 L8T 6.6L 401HP Crate Engine Tech Specs:

• Engine Type: Gen V Small-Block V-8 direct injection spark ignition
• Displacement: 400 ci (6.6L)
• Bore x Stroke: 4.060 in. x 3.860 in. (103.25 x 98 mm)
• Block: Cast-iron with 6-bolt nodular main bearing caps
• Crankshaft: Forged steel. 
• Connecting Rods: Forged powdered metal
• Pistons: Hypereutectic aluminum
• Camshaft Type: Billet steel hydraulic roller
• Valve Lift: .500 in. intake / .492 in. exhaust
• Camshaft Duration (@.050 in.): 193-degree intake / 199-degree exhaust
• Cylinder Heads: Aluminum, Rectangular Port Direct Injection
• Valve Size: 2.130 in. intake / 1.590 in. exhaust
• Compression Ratio: 10.8:1
• Rocker Arms: Investment-cast, roller trunnion
• Rocker Arm Ratio: 1.8:1
• Recommended Fuel: 87 octane
• Maximum Recommended rpm: 5600
• Reluctor Wheel: 58X
• Balanced: Internal

Engine Break-In Procedure

Use only engine oil that meets dexos1 specifications. For track events or competitive driving, use Mobil 1 15W-50 engine oil. Fill the engine with oil and follow the proper engine priming procedure.  Also check and fill as required any other necessary fluids such as coolant, power steering fluid, etc.

Start the engine and listen for any unusual noises. If no unusual noises are noted, run the engine at approximately 1000 RPM until normal operating temperature is reached.  The engine should be driven at varying loads and conditions for the first 30 miles or one hour without wide open throttle (WOT) or sustained high RPM accelerations.  Run five or six medium throttle (50%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear. Run two or three hard throttle (WOT 100%) accelerations to about 4000 RPM and back to idle (0% throttle) in gear. 

Change the engine oil and filter. Inspect the oil and the oil filter for any foreign particles to ensure that the engine is functioning properly.  Drive the next 500 miles (12 to 15 engine hours) under normal conditions. Do not run the engine at its maximum rated engine speed. Also, do not expose the engine to extended periods of high load.  Change the oil and filter again, inspect the oil and oil filter for any foreign particles to ensure that the engine is functioning properly.

Emissions Note:

This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

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