Made for naturally aspirated engine applications, the ATK SP26-G4 Chevy LQ9 Gen IV 408 Short Block features cast iron engine block, forged aluminum piston and forged steel connecting rod. This short block includes upgraded ARP main studs, and ARP 8740 rod bolts for enhanced reliability. This short block is fully balanced for reduced vibration and smooth running.

Short Block Specification

• Block: GM 6.0L Iron Gen IV
  
• Bore/Stroke: 4.030 x 4.000
  
• Displacement: 408 C.I.D.
  
• Crankshaft: Manley 4340 Forged 4.000" Stroker Internally Balanced 58 Tooth
  
• Connecting Rods: Manley 4340 Forged H Beam 6.125" ARP 8740 Bolts
  
• Pistons: Manley 2618 Forged -10cc Dished
  
• Piston Rings: Moly Rings
  
• Compression Ratio: 64cc = 11.2:1 / 68cc = 10.7:1 / 72cc = 10.3:1 (can vary due to deck height/gasket thickness)
  
• Camshaft Bearings: Installed & Clocked to OEM Position
  
• Freeze Plugs: Brass Installed & Sealed
  
• Oil Galley Plugs: Installed & Sealed
  
• Weight:285
  

Every great build needs a solid foundation! For that reason, we take the hard work out of the picture by selling short blocks that are ready for you to complete yourself. Our GM Short Blocks are most commonly packaged as the engine block assembled with Pistons, Piston Rings and Crankshaft installed.

ATK specializes in muscle. With the highest quality internal parts and Dyno Proven combinations of every engine built, ATK is able to add the most bang for your buck and back it up with an industry leading warranty.

Don't forget the engine paint!