Made in USA
High-Performance Short Block GM LS 408ci
InfoVehicle Info Needed
ATK ENGINESPART NUMBER: 059-SP39-B

High-Performance Short Block GM LS 408ci

$5,29306
Core Charge: $41000
Truck Freight
ShippingShips on 01/20/2027
Lowest PriceLowest Price Guarantee

Items You Need

Engine Assembly Lube [4 oz. Bottle]

JEGS

Engine Assembly Lube [4 oz. Bottle]

Part Number : 555-28000
$599$6.99
You Save$1.00
Break-In/Engine Oil Supplement [12 oz. Bottle]

JEGS

Break-In/Engine Oil Supplement [12 oz. Bottle]

Part Number : 555-28060
$1009$11.99
You Save$1.90
10295 Oil Pump Stock Volume High Pressure for GM LS

MELLING

10295 Oil Pump Stock Volume High Pressure for GM LS

Part Number : 689-10295
$15599
19212593 Muscle Car Oil Pan Kit for GM Gen III/IV LS Engine Swaps

CHEVROLET PERFORMANCE

19212593 Muscle Car Oil Pan Kit for GM Gen III/IV LS Engine Swaps

Part Number : 809-19212593
$32199

Gen III/IV LS 24 Tooth
High-Performance Short Block
  • GM LS 408ci Stroker
  • Cast Iron 6.0L LQ4 Block
  • 4340 Forged Crankshaft 24 Tooth
  • 4340 Forged H Beam Rods
  • 2618 Forged Flat Top Pistons +4cc
  • Built for Engines Running Boost

    ATK Core Return Process
    JEGS and ATK appreciate your business and want to ensure that your core return is as smooth as possible.

    Please CLICK HERE for ATK Core Return Process

     

    NOTE:

    • Core return can be any Chevy LS 6.0L engine

    This short block is built for engines that are going to be running boost or nitrous. It has upgraded ARP main studs, rod bolts, and Total Seal piston ring package gapped accordingly for 10+ PSI.

    Block Information:

    • Seasoned OE 2001-2007 GM Cast Iron LQ4 6.0L with ARP main studs
    • Bore/Stroke: 4.030" x 4.000"
    • Displacement: 408ci
    • Camshaft Bearings: Installed and clocked to OEM position
    • Freeze Plugs: Installed and sealed
    • Oil Galley Plugs: Installed and sealed

    Rotating Assembly:

    • Crankshaft: Manley 4340 forged 24-tooth reluctor wheel
    • Rods: Manley 4340 forged H beam rods with ARP 2000 bolts
    • Compression Ratio: 64cc= 11.9:1 68cc= 11.4:1 / 72cc= 11.0:1 
    • Pistons: Manley 2618 flat top +4cc
    • Rings: Total Seal CS AP with steel top rings gapped for boost/nitrous

      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

    Notes:

    ATK's Boost/Nitrous short blocks are meant for engines running these setups. Bearing clearances and ring gap have been taken into consideration for this series of short blocks.

    Emissions Note:

    This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

    CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART

    Please CLICK HERE for ATK Warranty

    • Short Blocks for Street or Strip

      ATK Engines High-Performance Short Blocks provide the foundation for your next engine build for Gen I Small Block Chevys, Big Block Chevys, and Gen III/IV LS. These short blocks support mild to extreme horsepower in naturally aspirated or boosted applications.

    Part TypeEngine Short Block
    Product LineATK Engines Small, Big Block Chevy & LS Short Blocks
    BrandATK ENGINES
    Package Height26.0
    Package Width26.0
    Package Length29.0
    Weight342.0 PG
    Part CategoryPerformance Parts
    QuantitySold individually
    Part FitmentSemi Universal
    Vendor Part NumberSP39-B
    Package Qty1
    Package TypeEA
    No Questions
    No Reviews
    Some parts are not legal for use in California or other states with similar laws / regulations
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