The ATK SP40-G4-B Chevy LQ9 Gen IV 408 Short Block is the heart of nitrous-boosted engines. It contains fully forged and balanced components for impeccable and superior performance. This short block has upgraded ARP main studs, rod bolts, and Total Seal piston ring package that are perfectly gapped for 10+ PSI.
- 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 24 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 = 9:1 / 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 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.
ATK High Performance Chevy LS 408 Short Blocks
• Oil: 5W30
• Harmonic Balancer/Damper: Internally Balanced
• Flex Plate / Flywheel: Internally Balanced
• Head Gasket: .051"
• Balancer: Internal balance
• Flexplate/Flywheel: Internal balance
• Head Gasket: .051" thickness or per application
• Oil: 10W40 Non synthetic for first 3000 miles
• Oil Filter: Wix or K&N per application
• Oil Pump: Melling #689-10295 with high pressure spring
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 is free and lift gate will be provided.
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