ATK Chevy LQ9 Gen IV 408 Boost/Nitrous Short Block 58 Tooth -29cc Dished SP36-G4-B

Item #22691 Brand:ATK Engines

Made in the USA
ATK Chevy LQ9 Gen IV 408 Boost/Nitrous Short Block 58 Tooth -29cc Dished SP36-G4-B
ATK Chevy LQ9 Gen IV 408 Short Block 58 Tooth
* ** FREE SHIPPING on ATK Engines. This item ships directly from the manufacturer and is not available for store pickup. Some engines are made-to-order or can be backordered. Delivery can be delayed up to 5 to 6 weeks but typically ship within 2 weeks.
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This ATK Chevy LQ9 Gen IV 408 replacement short block is designed for high-demanding engines. It includes Manley 2618 forged pistol and Total Seal CS AP with steel top ring gapped to meet the needs of engines used for boost or nitrous applications. This short block comes installed with camshaft bearings, freeze plugs and oil galley plugs.

Short block Specifications:

  • 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 2000 Bolts
  • Pistons: Manley 2618 Forged -29cc Dished
  • Piston Rings: Total Seal CS AP with Steel top ring gapped for nitrous/boost
  • Compression Ratio: 64cc = 9.3:1 / 68cc = 9.0:1 / 72cc= 8.7:1 (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 High Performance Engines LQ9 Gen IV 408 Boost/Nitrous Short Block


Engine Information:

• Oil: 5W30
• Harmonic Balancer/Damper: Internally Balanced
• Flex Plate / Flywheel: Internally Balanced
• Head Gasket: .051''

Disclaimer: The parts listed are ATK’s recommendations of parts to be used to obtain our power figures listed. Power figures can vary based on parts used by the end user. It is the customer’s responsibility to verify components will work for their application. Some modifications to the vehicle may be required using these and or other aftermarket parts.

Shipping Information

Shipping is free and lift gate will be provided.

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