This 427 c.i. GM LS Compatible Standard Edition Builder Series engine and transmission package is rated at 585 horsepower and 520 lb-ft of torque. It is built on a BluePrint Engines High Strength Cast Iron (LSX Style) Block (6 Bolt Main, 4.0665" Bore) and topped with LS3 Aluminum Cylinder Heads. The package pairs the engine with a 4L65/70E automatic transmission.

BluePrint Engines BLS4278K4L7 Engine and Transmission Package Features:

• 585 hp and 520 lb-ft of torque
• 11.0:1 compression ratio
• Camshaft: Hydraulic Roller - .624 Intake / .624 Exhaust Lift - 239 Intake / 255 Exhaust Duration [email protected] LSA
• Rotating assembly: Forged Crank, 4.125 in. Stroke and Forged 6.125 in. Rods, forged pistons
• Cylinder heads: LS3 Aluminum Cylinder Heads
• Intake: BluePrint Engines Cast Aluminum Intake, Holley Terminator EFI
• Transmission: 4L65/70E automatic
• Pulley kit: Natural - LT1 Style 150amp Alternator, LT1 Style Water Pump, Type II Power Steering Pump with Reservoir, Compact Style Air Conditioning Compressor

BluePrint Engines BLS4278K4L7 Installation Notes:

• Recommended fuel: 91+ Octane
• Timing: ECM Supplied with Calibration
• Firing order: 1,8,7,2,6,5,4,3
• Recommended torque converter stall speed: 2200+ RPM
• Recommended flexplate/flywheel: Non Weighted BPP12654640 - BPPLS1611
• Recommended harmonic balancer: Non-Weighted
• Engine balance: Internally Balanced
• Recommended spark plug: CCH9405, gapped at .045 in.
• Air cleaner is not included