The LS3 427’s heart and soul is the new 4.065 aluminum block.  The LS3 designation has a Mast Motorsports engineered camshaft that is custom ground on a Mast Motorsports LS3 cam core.  The 427 foundation is a honed and decked LS3 aluminum block with a forged Callies rotating assembly with Mahle pistons that is topped off with Mast Motorsports CNC LS3/L92 heads and a LS3 intake manifold.  ARP fasteners are used throughout and Manley pushrods ride on LS3 hydraulic roller lifters.  The LS3 427 is the first release of a diverse line of Mast Motorsports 427 Turnkey Crate Engines that are designed for Marine, Muscle Car, Off Road, and Sand Car markets.  The LS3 427 HO has a decent lope at idle and peaks at the 620+ horsepower mark. The powerful fuel injected turnkey crate engine is tuned for the street to run on 93 octane and includes an ECM and wiring harness with knock control to adjust timing if 87 octane fuel is used.

Specs:  
Type:    LS3 7.0L
Displacement:  427 Cubic Inches
Compression Ratio:  10.8:1
Bore x Stroke:  4.070 x 4.100
Rev Limit:   7000 RPM
Crank:   Callies
Rods:   Callies
Pistons:   Mahle Motorsports
Cam:   Mast LS7 Core Custom Cam
Heads:   Mast CNC LS3/L92 Heads
Intake:   GMPP L76/L92 Intake
Valve Springs:  Pac 1518 Nitrided Beehive

 
LS3 Aluminum Block
Plateau Honed to 4.070
True Surfaced Deck
Engine Block Deburred
Blueprinted Shortblock
GM Car Harmonic Damper
ACL Rod and Crank Bearings
Callies 4.100 Stroked Crankshaft
Callies Compstar Connecting Rods
Custom Mahle Motorsports Pistons
Mast Motorsports CNC LS3/L92 Cylinder Heads
ARP Head Bolts
ARP Main Studs
Cometic Head Gaskets
Mast LS3 Core Custom Hydraulic Roller Cam
LS3 Hydraulic Roller Lifters
Manley 1 Piece Chrome Molly Pushrods
Pac 1518 Nitrided Beehive Valve Springs
M-90 Calibrated ECM
Main Wiring Harness
Dash Harness
Air Mass Harness
Trans Harness
EGO Harness
Bosch EGO Sensor
Fuel Pump Harness
Fan Harness
LS3 Intake
GM 90mm DBW Throttle Body
Bosch Dead Headed Fuel Rail
Bosch LS3 Fuel Injectors
Mast 8 Layer Air Filter with IAT Bung
Intake Air Temperature Sensor 560-2218 | info@
Crankshaft Position Sensor
Camshaft Position Sensor
Oil Pressure Sensor
Oil Temperature Sensor
Engine Coolant Temperature
Engine Knock Sensors
Manifold Air Pressure Sensor
Ignition Coils
Spark Plugs
Plug Wires
GM Foot Pedal
GM Starter
Car Water Pump
LS3 Oil Pan
GM Oil Filter
Mobile 1 Synthetic Oil
Engine Break in Oil Additive