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These ATK High Performance Chevy LS 408 short blocks are made to handle some serious power. The foundation of any high performance engine is a rock-solid short block, so ATK designed and developed these to be just that. They feature a fully forged, balanced, and blueprinted rotating assembly that is available in a variety of configurations to fit naturally aspirated, nitrous, and forced induction builds, as well as those with 24 and 58-tooth cranks. These ATK High Performance Chevy LS 408 short blocks include the following: * GM LS Iron blocks * Aligned and hone main bores * Manley 4340 forged crankshaft * 4.00 in. stroke * Manley 4340 H-beam connecting rods * Manley forged pistons
( 4 )
$4,828.99
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$5,143.99
ATK High Performance Chevy LQ9 6.0L short blocks with OE flat top pistons are great beginnings for your mild street build, or just as a replacement for a tired short block. ATK takes the hard work out of your project by selling blocks that are ready to complete yourself. Every great build needs a solid foundation. Start yours with one of ATK's Chevy LQ9 6.0L short blocks. Technical specifications: * Block: Seasoned 6.0L cast no. 364 or 184 * Bore/stroke: 4.030 x 3.622 * Year range: 2001-2007 * Displacement: 370 c.i.d. * Crankshaft: OEM GM 3.622 in. stroke internally balanced 24-tooth reluctor wheel * Connecting rods: OE GM forged powder metal 6.093 in. stock bolts * Pistons: OE hypereutectic flat top with no valve reliefs * Piston rings: Moly rings * Compression ratio: 64cc = 10.7:1, 68cc = 10.2:1, 72cc = 9.8:1 * Camshaft bearings: Installed and clocked to OEM position * Freeze plugs: Brass installed and sealed * Oil galley plugs: Installed and sealed * Weight: 285 lbs.
( 6 )
$3,198.99
ATK High Performance Chevy LQ4 6.0L 460 hp long block crate engines lay down impressive power that can be run with factory fuel injection or retrofitted with a carburetor. They're hand-built, balanced, and blueprinted using top-quality parts. Don't waste time trying to salvage a high-mileage short block when you can get a fresh mill that's ready for your choice of components to make it your own. ATK Chevy LQ4 6.0L 460 hp long block crate engines include: * Handpicked and seasoned 6-bolt main block * Aligned and honed main bores * OE steel crankshaft * 3.622 in. stroke * OE connecting rods * Hypereutectic dish top pistons * Aluminum cylinder heads * Hydraulic roller camshaft * Timing chain and gear set * 1.7:1 ratio rocker arms * 24-tooth reluctor
( 10 )
$5,049.99
ATK Chevy LM7 383 short blocks support your build with a solid foundation. Produced for the 1999-2007 trucks, LM7 engines are very popular engines to swap into musclecars and other LS swap vehicles. ATK High Performance Chevy LM7 383 short blocks are built for naturally aspirated engines up to 700 hp. Your ATK LM7 engine may include these components for optimal performance: * Block: GM LM7 5.3L * Bore/stroke: 3.903 x 4.000 * Displacement: 383 cu. in. * Crankshaft: K1 4340 forged steel, internally balanced 24-tooth * Connecting rods: Scat Premium Pro 4340 forged I-beam with ARP 8740 bolts * Pistons: Wiseco 2618 forged aluminum with coated skirts * Piston rings: Wiseco GFX (alloy steel top ring) * Camshaft bearings: Installed and clocked to OEM position * Freeze plugs: Brass installed and sealed * Oil galley plugs: installed and sealed * Weight: 285 lbs.
Not Yet Reviewed
$4,098.99
ATK high performance LS3/L92 25cc as cast aluminum cylinder heads are the perfect budget option for your next LS build. These fully assembled heads are capable of making over 600 hp naturally aspirated out of the box and will come loaded with upgraded components. The springs are set up to be used on up to .650 in. lift camshafts. No reason to swap parts on your new heads when running an upgraded cam! -- Features and benefits: * Bronze valve guides * Dual valve springs for .650 in. max lift * CNC-finished faces and bolt holes for extreme accuracy * 355-T6 high density aluminum * Machined for screw in studs and guide plates * All factory components will fit without modification -- Cylinder Head Specifications INTAKE: * Intake Runner Volume (cc): 252 * Intake Port Location: Standard * Intake Valves Included: Yes * Intake Valve Diameter (in): 2.160 in. EXHAUST: * Runner Volume (cc): 78.8 * Exhaust Valve Diameter (in): 1.600 in. * Exhaust Valves Included: Yes * Exhaust Runner: No * Port Shape: Round * Exhaust Port Location: Standard COMBUSTION CHAMBER: * Combustion Chamber Volume (cc): 69.4 * CNC-Machined Combustion Chamber: No VALVE SPECS: * Intake Valve Angle: 12 degrees (3 degrees rolled) * Exhaust Valve Angle: 12 degrees (3 degrees rolled) * Valve Guides Included: Yes * Valve Guide Material: Manganese Bronze * Valve Seats Machined: Yes * Valve Seat Machine Style: 5-Angle * Valve Seat Material: Chrome Nickle * Valve Stem Seals Included: Yes * Valve Stem Seal Style: Viton® Fluoroelastomer SPRINGS: * Valve Springs Included: Yes * Maximum Valve Lift (in): .650 in. * Spring Pressure Open: 370 @ 1.150 * Spring Pressure Closed: 142 @ 1.800 * Outside Diameter of Outer Spring (in): 1.29 in. * Damper Spring Included: Yes * Number of Springs per Valve: Dual * Retainers Included: Yes * Retainer Material: Chromoly Steel * Locks Included: Yes * Lock Style: 7 Degree ROCKER ARMS: * Rocker Arm Studs Included: No * Rocker Arms Included: N/A * Rocker Arm Nut Thread Size (in): 8 x 1.25 * Rocker Arm Nuts Included: No MISC: * Head Style: Assembled * Cylinder Head Material: Aluminum * Cylinder Head Finish: Natural * Spark Plug Style: Standard * Cover Mounting Style: Standard * Steam Holes Drilled: No * Oiling Style: Through Pushrod * Machined for O-Ring: No * Heat Crossover: No * 10mm Accessory Bolt Holes Machined On Ends of Heads
Not Yet Reviewed
$748.99
With ATK High Performance Chevy LM7 5.3L 385 hp long block crate engines expect big mid to upper end power and a noticeable idle. They were designed to be performance upgrades for a 1999-2007 Chevy truck LM7 or an LS swap in a hot rod. Technical specifications include: * Horsepower: 385+ * Torque: 390+ * Block: GM 5.3L iron LM7 * Bore/stroke: Up to 3.809 x 3.622 * Year range: 1999-2007 * Displacement: 323 c.i.d. * Crankshaft: OEM GM 3.622 in. stroke internally balanced 24 tooth reluctor wheel .857 in. flange * Connecting rods: OE GM forged powder metal 6.093 in. stock bolts * Pistons: Hypereutectic dish * Piston rings: Moly rings * Compression ratio: 9.5:1 compression * Camshaft: Hydraulic roller * Camshaft specifications: Custom grind * Camshaft bearings: Installed and clocked to OEM position * Cylinder heads: OE aluminum 61.15cc 1.89/1.55 * Freeze plugs: Brass installed and sealed * Rocker arms: OE powdered metal 1.7 ratio * Oil Galley plugs: Installed and sealed * Weight: 385
( 15 )
$4,189.99
Start your next engine build with one of these ATK High Performance Chevy LQ4 6.0L short blocks. The LQ4 is an ultra-tough basis for high-horsepower engines in their stock form, but ATK improved on it. These engines are hand-built, balanced, and blueprinted using top-quality parts. Don't waste time trying to salvage a high-mileage short block when you can get a fresh mill that is ready for your choice of components to make it your own. These ATK High Performance Chevy LQ4 6.0L short blocks include the following: * Handpicked and seasoned 6-bolt main block * Aligned and honed main bores * OE steel crankshaft * 3.622 in. stroke * OE connecting rods * Hypereutectic dish top pistons
( 1 )
$3,198.99
ATK Chevy LM7 5.7L/347 short blocks provide a solid foundation for your build. Produced for the 1999-2007 trucks, LM7 engines are very popular engines to swap into musclecars and other LS swap vehicles. ATK High Performance Chevy LM7 5.7L/347 short blocks are built for naturally aspirated engines up to 700 hp. Your ATK LM7 engine may include these components for optimal performance: * Block: GM LM7 5.3L * Bore/stroke: 3.903 x 3.622 * Displacement: 5.7/347 c.i.d. * Crankshaft: OE reground 3.622 in., internally balanced 24-tooth * Connecting rods: Scat Premium Pro 4340 forged I-beam with ARP 8740 bolts * Pistons: Wiseco 2618 forged aluminum with coated skirts * Piston rings: Wiseco GFX (alloy steel top ring) * Camshaft bearings: Installed and clocked to OEM position * Freeze plugs: Brass installed and sealed * Oil galley plugs: installed and sealed * Weight: 285 lbs.
( 2 )
$3,298.99
ATK High Performance 250cc LS1/LS6 aluminum assembled engine cylinder heads are complete new builds. They include valves, valve springs, valve spring retainers, valve stem seals, and soft plugs. All threads are checked and repaired, if necessary; and all passages and part interfaces are pressure checked. Product specifications: * Material: A356 aluminum * Bolt count: 6-bolt head * Intake port volume: 250cc * Intake port dimension: 3.227 in. H x 1.119 in. W * Intake port location: Stock cathedral port * Intake valve size: 2.080 in. * Intake valve material: Stainless steel * Exhaust port volume: 105cc * Exhaust port dimension: 1.628 in. H x 1.722 in. W * Exhaust port location: .086 in. raised * Exhaust valve size: 1.60 in. * Exhaust valve material: Stainless steel * Combustion chamber size: 61cc * Valve cover bolt pattern: Perimeter bolt * Valve angle: 11 degree * Valve spring pocket diameter: 1.610 in. O.D. * Valve spring pac: 1905 dual spring (hydraulic roller) * Valve spring setup height: 1.800 in. * Valve spring closed pressure: 160 lbs. (with retainer) * Valve spring open pressure: 1.200 in., .600 in. lift, 425 lbs. / 1.150 in., .650 in., lift 445 lbs. (with retainer) * Valve spring max lift: .650 in. * Valve guide material: Manganese bronze * Valve seal material: Viton© * Valve seat material: Powder metal * Retainer material: Titanium * Deck thickness: .750 in. * Minimum bore diameter: 3.900 in. (will not fit stock bore 4.8L/5.3L) * Flat mill: .006 in. per cc * Spark plug dimensions: 14mm x .708 in. with tapered seat * Torque specifications per application based on factory or aftermarket bolts/studs
Not Yet Reviewed
$998.99
ATK offers select parts for your build, including cylinder heads. They use them in their engine combinations and are available to complete your LS engine or upgrade existing components. ATK High Performance 260cc LS3 CNC-ported cylinder head features: * A356 aluminum construction * Stainless steel intake and exhaust valves * Manganese Bronze valve guides * Viton® valve seal * Powder meatal valve seats * Titanium retainers * Spark plug dimensions: 14mm x .708 in. with tapered seat
Not Yet Reviewed
$1,148.99
ATK offers select parts for your build, including cylinder heads. They use them in their engine combinations and are available to complete your LS engine or upgrade existing components. ATK High Performance 270cc LS3 CNC-ported cylinder head features: * A356 aluminum construction * Stainless steel intake and exhaust valves * Manganese Bronze valve guides * Viton® valve seal * Powder meatal valve seats * Titanium retainers * Spark plug dimensions: 14mm x .708 in. with tapered seat
Not Yet Reviewed
$1,198.99
Big power requires a solid foundation, so start your next build with one of these ATK High Performance Chevy 427 Dart Race Series short blocks. These short blocks are built, balanced, and blueprinted to be the strongest and most reliable short block available for your race car or hardcore street car. These ATK High Performance Chevy 427 Dart Race Series short blocks include the following: * Dart SHP block * Aligned and honed main bores * 4340 forged crankshaft * 4.00 in. stroke * 4340 forged H-beam connecting rods * Forged flat-top pistons
Not Yet Reviewed
$9,249.99
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