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MTM111-423 -Mast Motorsports Turn-Key Black Label 440 LSX with FAST Intake (685hp), Includes M-120 WBO2 ECM and Harness

This product may require vehicle validation(s) for proper fitment. Please contact us to confirm correct vehicle fitment and usage.

Availability: Item has been discontinued and is no longer available
Shipping: FREE 48 State Shipping


Type: X-Block 7.2L
Displacement: 440 Cubic Inches
Compression Ratio: 12:1
Bore x Stroke: 4.185 x 4.000
Rev Limit: 7250 RPM
Crank: Callies Forged
Rods: Callies H-Beam
Pistons: Mahle Motorsports
Cam: Mast Custom 3-Bolt Core Cam
Heads: Mast 12 degree CNC LS7 Heads
Intake: FAST LS7 Intake
Valve Springs: Mast Double Nitrided .700 Lift

Part Number: 111-423

Application List



  • 111-423
  • 111-423
  • Mast Motorsports
  • Item has been discontinued and is no longer available
  • New


Shipping Information

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

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