MTM1XX-126 Mast Motorsports LS7 440 Aluminum Short Block

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


LS7 440CID Short Block, 11.2:1 Compression Ratio (based on 70cc Heads), 4.070" Bore x 4.000" Stroke

Mast Motorsports is now proud to offer expertly hand assembled LS short blocks for customers wanting a premium foundation for their engine projects. Each short block is align honed with torqued ARP main studs then decked on their CNC machine with their precision fixturing. The block is then plateau honed, deburred, and washed. Dura Bond cam bearings, ACL main bearings, and ACL rod bearings are utilized for each Mast Motorsports assembly. Using only the highest quality forged rotating assembly components from Callies, and Mahle that meets Masts strict tolerances ensure their short blocks are the highest quality available on the market. Currently LS3, LS7, and X-blocks are available from 416 to 454 cubic inches. Assemblies are available with either a 24 or 58 tooth reluctor wheel and are available with the combination of forged Callies crank and forged Callies H-Beam connecting rods. Mahle Motorsports forged pistons are also used exclusively in every Mast short block.

Mast Motorsports short blocks include the following:

  • GM Bare Block
  • Forged Callies Compstar Crank
  • Forged Callies Compstar H Beam Rods
  • Mahle Forged & Coated Pistons
  • ARP Main Studs
  • ACL Main & Rod Bearings
  • GM Gen IV Oil & Coolant Plugs
  • Application List



    • 1XX-126
    • 1XX-126
    • Mast Motorsports
    • Item has been discontinued and is no longer available
    • New


    Shipping Information

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

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