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ATK Chevy LS 408 Boost/Nitrous Short Block 24 Tooth – 18cc Dished SP38-B

ATK Chevy LS 408 Boost/Nitrous Short Block 24 Tooth – 18cc Dished SP38-B

Item #22698

SP38-B ATK Chevy LS 408 Boost/Nitrous Short Block 24 Tooth -18cc Dished
Quantity: close
Only $4,398.75

• This item ships directly from the manufacturer

• Expected delivery time is 1 – 2 weeks

• Not available in Eastwood Retail Stores

• Order may not be changed or canceled



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Build the perfect engine for your muscle machine using this ATK SP38-B Chevy LS 408 Short Block. It is suited for engines that will be used with boost or nitrous. Fully forged components along with updated ARP main studs, ARP 2000 rod bolts and Total Seal CS AP ring package enable high-powered performance.

Short Block Specification

  • Block: GM 6.0L Iron LQ4
  • 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: 2618 Forged +18cc Dished
  • Piston Rings: Total Seal CS AP Steel Top Ring
  • Compression Ratio: 64cc=10.2:1/66cc=10.0:1/70cc=9.6:1
  • 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!
Engine Paint

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ATK High Performance Chevy LS 408 Short Blocks


Engine Information:

• Oil: 5W30
• Harmonic Balancer/Damper: Internally Balanced
• Flex Plate / Flywheel: Internally Balanced


Click Here to view ATK Engines Warranty


Recommended Components:

• 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 Instructions

Shipping is free and lift gate will be provided.

Eastwood Offers Free Lifetime Technical Support

Click here for product SDS information

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