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GM 427 LS Series • Base Fuel Injected Drop-in • Aluminum Heads
HP & Torque: 625 HP / 565 FT LBS Dyno Proven
Compression Ratio:
Aluminum Heads
Forged Pistons
Roller Cam
Forged Crank
Part #: PSLS4271CT


New GM LS3/L92 Aluminum Block!

Rotating Assembly:

Forged Steel Crankshaft
Forged Mahle Pistons
Forged I Beam Rods
Mahle Performance Rings
Balanced Rotating Assembly
Hydraulic Roller cam
Premium Single true roller timing set
GM factory roller rockers with upgraded full roller trunion

Cylinder Heads:

New BluePrint Aluminum Cylinder Heads - PS8015
Chrome moly retainers and spring locators
Dual coil .650" lift valve springs
2.165 intake valves
1.590 exhaust valves
Hardened push rods

Cam Specs:

Cam Type:
Roller - .624 intake .624 exhaust lift, 239 intake 255 exhaust duration @ .050, 114 degree lobe sep.

Ignition Timing:

ECM Controlled (not included – customer sends
their original ECM to BluePrint for reprogramming

Also Includes:

Timing cover
LS3 Intake manifold


30 month / 50,000 mile


This engine requires a non-weighted harmonic balancer, and non-weighted flexplate/flywheel.
Recommended Fuel: 91 Octane
BluePrint Engines recommends a 2200+ RPM stall converter.


This engine is specifically designed to replace your existing LS engine - a direct drop in for Gen 4 applications. Built with a 58x Gen 4 style reluctor and sensors. Also included is a free retune of your ECM - Contact BluePrint Engines for detail


Not for use in pollution controlled vehicles.

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