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MTM117-450 - Mast Motorsports LSX 427 WHIPPLE 2.9 Supercharged (750hp), NO ECM or Harness

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Availability: Special Order Item
Shipping: FREE 48 State Shipping
Pricing: $22,320.95

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The X-Block 427 HO SC’s heart and soul is the new GM Performance X-block. This X-block engine family utilizes a Mast Motorsports engineered camshaft that is custom ground on a Mast Motorsports 3 bolt cam core. The 427 HO’s foundation is a fully machined X-block with a forged Callies rotating assembly with Mahle pistons that is topped off with Mast Motorsports CNC LS3 casting cylinder heads and a Whipple 2.9L Supercharger. ARP fasteners are used throughout and Mast Black Label pushrods ride on GM Cadillac High RPM hydraulic roller lifters. This hand built X-block based engine utilizes a camshaft that has a moderate lope that creates great RPM power across the band for the customer that will be aggressively racing their vehicle, but still wants great street manors for a daily driver.

Type: X-Block 7.0L W2.9
Displacement: 427 Cubic Inches
Compression Ratio: 9.5:1
Bore x Stroke: 4.125 x 4.000
Rev Limit: 7000 RPM
Crank: Callies Forged
Rods: Callies H-Beam
Pistons: Mahle Motorsports
Cam: Mast Custom 3-Bolt Core Cam
Heads: Mast Black Label LS3 Heads
Intake: Intercooled Supercharger
Valve Springs: Mast Dual

Engine Components:

  • LSX GMPP Block
  • Plateau Honed to 4.125”
  • True Surfaced Deck
  • Engine Block Deburred
  • Blueprinted Short block
  • Clevite Rod and Crank Bearings
  • Callies 4.000” Stroked Crankshaft
  • Callies Forged H-Beam Connecting Rods
  • Custom Mahle Motorsports Pistons
  • Mast Black Label 11 Degree LS3 Heads
  • Stainless Intake Valve
  • Inconel Exhaust Valve
  • ARP Head Bolts
  • ARP Main Studs
  • Cometic Head Gaskets
  • Mast 3-Bolt Core Hydraulic Roller Cam
  • LS3 Hydraulic Roller Lifters
  • Mast Black Label Pushrods
  • Mast Dual Valve Springs
  • Dash Harness
  • MAP/IAT Harness
  • Trans Harness
  • EGO Harness
  • Bosch EGO Sensor
  • Fuel Pump Harness
  • Fan Harness
  • Whipple 2.9L Supercharger
  • GM 90mm DBW Throttle Body
  • Custom LS7 Style 85lb/hr Fuel Injectors
  • Dual Nipple Boost Bypass Diaphragm
  • Electronic Solenoid for Boost Control
  • Ultra Heavy Duty Belt Tensioner
  • Mast 8 Layer Air Filter with IAT Bung
  • Intake Air Temperature Sensor
  • Crankshaft Position Sensor
  • Camshaft Position Sensor
  • Oil Pressure Sensor
  • Oil Temperature Sensor
  • Engine Coolant Temperature
  • Engine Knock Sensors
  • Throttle Outlet Pressure Sensor
  • Manifold Air Pressure Sensor
  • Ignition Coils
  • Spark Plugs
  • Plug Wires
  • GM Foot Pedal
  • GM Starter
  • GM Oil Filter
  • Break In Engine Oil
  • Engine Break in Oil Additive
  • Powerbond SFI Approved Y-Body Damper
  • Choice of F-Body, Y-Body, or Truck Water Pump, Balancer and Oil Pan
  • Application List



    • 117-450
    • 117-450
    • Mast Motorsports
    • Special Order Item
    • New

    Shipping Information

    • Item Requires Shipping
    • 500.0 lbs.
    • FREE 48 State Shipping

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