Iron 408 Black Label Long Block

  • Sale
  • $ 11,995.00


The Iron 408's heart and soul is the new 4.005 iron block.  The 408 designation has a Mast Motorsports engineered camshaft that is custom ground on a Mast Motorsports billet cam core.  The 408 Black Label's foundation is a honed and decked LY6 iron block with a 4.000” forged Callies Compstar crank and Compstar rods.  It includes Diamond forged pistons and is topped off with Mast Black Label LS3 255 heads,  ARP fasteners are used throughout and Mast pushrods ride on LS7 hydraulic roller lifters.  The Iron 408 is just one of a diverse line of Mast Motorsports hand built engines that are designed for the Hot Rod/Muscle Car and Offroad markets.  The Iron 408 Black Label makes 600 horsepower and is competitively priced for such a powerful long block.

Type: LY6 6.7L
Displacement: 408 Cubic Inches
Compression Ratio: 11:1
Bore x Stroke: 4.005 x 4.000
Rev Limit: 7500 RPM
Crank: Callies Compstar
Rods: Callies H-Beam
Pistons: Diamond Racing
Cam: Mast Custom 3-Bolt Billet Core Cam
Heads: Mast Black Label LS3 255
Valve Springs: Mast Motorsports Dual

*All hp numbers will be within 2% of the advertised number.