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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
ATK offers select parts for your build, including cylinder heads. They use them in their engine combinations and are available to complete your big block Chevy engine or upgrade existing components. ATK High Performance 315cc BBC cylinder head features: * A356 aluminum construction * Stainless steel intake and exhaust valves * Manganese Bronze valve guides * Viton® valve seal * Powder meatal valve seats * Steel retainers with 10-degree locks * Spark plug dimensions: 14mm x .708 in. with gasket seat
Not Yet Reviewed
$1,048.99
Outfit your top end with a set of these assembled ATK High Performance aluminum cylinder heads for small block Chevrolet. They're cast, machined, and assembled with A356 aluminum alloy. The heads feature the latest port designs for maximum efficiency and increased power, and improved stock exhaust port location for better header fitment. ATK High Performance aluminum cylinder heads for small block Chevrolet include: * 2.020 in. stainless steel, swirl polished with undercut stem intake valves * 1.600 in. stainless steel, swirl polished with undercut stem exhaust valves * Manganese bronze valve guides * Alloy valve seats * 1.437 in. diameter valve springs (.600 in. max valve lift) * Chromoly 7-degree valve spring retainers * Single groove 7-degree valve locks * Valve spring locators * 5/16 in. flat pushrod guideplates * 3/8-24 in. rocker arm studs
Not Yet Reviewed
$798.99
ATK offers select parts for your build, including cylinder heads. They use them in their engine combinations and are available to complete your small block Ford engine or upgrade existing components. ATK High Performance 205cc SBF aluminum cylinder head features: * A356 aluminum construction * Stainless steel intake and exhaust valves * Manganese Bronze valve guides * Viton® valve seal * Powder meatal valve seats * Steel retainers with 7-degree bead lock keepers * Spark plug dimensions: 14mm x .750 in. with gasket seat * Head bolt diameter: 1/2 in.
Not Yet Reviewed
$698.99
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
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 High Performance GM 350 Vortec 290 hp Stage 3 long block crate engines are perfect replacements for your worn out SBC. They are designed with matched components for reliable performance with extra "go power", and they require an electric fuel pump. ATK Stage 3 or complete dressed engines are engineered for those wanting to drop the engine into their project and fire it up. They have outfitted the engines as completely as possible to save you time and headaches. Typically ATK GM 350 Vortec 290 hp complete long blocks consist of: * OE block bored to 4.060 in. diameter with 2-bolt mains and a one-piece rear main seal * OE reground crankshaft with a 3.480 in. stroke * OE powder metal 5.7 in. length connecting rods * Hypereutectic 9.4:1 compression ratio pistons * Moly piston rings * Hydraulic roller camshaft (191/194 duration at 50, .414/.428 in. lift, 111 LSA) * Cast iron Vortec cylinder heads with 64cc combustion chambers, 165cc intake runners, and come with 1.94 in./1.5 in. valves. * Stamped steel 1.5 ratio rocker arms * Single roller timing set * 5 qt. oil pan ( will not fit Chevelle with steering behind crossmember, some Corvettes, and 1962-67 Chevy II) * Melling standard volume oil pump * Valve covers * Flexplate * ATK HP dual plane intake manifold * Distributor HEI * Cast iron long water pump * Front Powerbond balancer (internally balanced) * Pioneer externally balanced 168 tooth flexplate * Quick Fuel Brawler 670cfm carburetor * Autolite spark plugs (605) with 8mm wires
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$3,625.99
ATK High Performance GM 350 345 hp/400 lbs.-ft. Stage 1 long block crate engines are classics with great street manners, and vacuum to power all your accessories. These Stage 1 or base engines are designed for those that may have their own component parts already, and who also are interested in completing out the build themselves. Typically ATK GM 350 345 hp base long block engines consist of: * Seasoned OE short block with 4-bolt mains * OE cast crankshaft * OE 5.7 in. powder metal connecting rods * Hypereutectic pistons * Moly piston rings * Hydraulic roller camshaft * 220/224 at .050 in. * .495 in./502 in. lift 110 LSA * ATK cast iron cylinder heads * 76cc combustion chambers * 165cc intake runners * 1.94 in./1.5 in. valves * Stamped steel 1.5 ratio rocker arms * Valve covers * Timing set and cover * Oil pan, high volume oil pump with pick-up tube
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$3,198.99
Give your ride new life with ATK High Performance GM 350 330 hp/380 lbs.-ft. Stage 1 long block crate engines. These engines are based on the tried-and-true small block Chevy and are built to perform right out of the box. ATK hand-assembles and balances each engine using top-quality parts to help them produce awesome power. Whether you are replacing an older, worn down engine or just looking for a little more performance, ATK has you covered. Stage 1 long block crate engines include: * Handpicked, remanufactured blocks * ATK cast iron cylinder heads * 76cc chambers * 165cc intake runners * 1.94 in./1.5 in. valves * Stamped steel 1.5 ratio rocker arms * OE crankshaft * OE 5.7 in. powder metal connecting rods * Hypereutectic flat-top pistons * Moly rings * Hydraulic flat tappet camshaft * 465 int./.488 exh. cam lift * 224 int./234 exh. cam duration at 0.50 * 9.1:1 compression * Valve covers * Timing cover and timing set * Oil pan, pump, and pickup tube
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$3,099.99
Bring your ride to life with ATK High Performance Ford 302 375 hp Stage 1 long block crate engines. These engines are based on the tried and true Ford 302 and are built to perform. ATK hand-assembles and balances each engine using top-quality parts to help them produce awesome power. Whether you are replacing an older, tired engine or just looking for a little more performance, ATK has you covered. Details and specs: * 375 hp/380 lbs.-ft. * Compression Ratio: 9.5:1 * ATK Aluminum heads * Hydraulic roller cam * Cast steel crankshaft 50oz external balance * Hypereutectic pistons * Seasoned OE roller block 1987-1995 * 4.040 in. bore x 3.000 in. stroke * One-piece rear main seal * Mechanical fuel pump provision * Dual sump oil pan HP08, Front sump oil pan HP78 * Melling high volume oil pump * Double roller timing set Cylinder Heads: * ATK aluminum cylinder heads * 58cc chamber * 2.02 in. intake/1.60 in. exhaust valves * 185cc intake runners * 1.6 aluminum roller rockers Roller Cam specs: * .512 intake/.512 exhaust * 220 intake/224 exhaust duration @ .050 - 112-degree lobe separation Recommended: * 34-36 degrees total timing * 13726548 firing order * Left Hand inlet reverse rotation water pump (HP08) * Right Hand inlet standard rotation water pump (HP78) * Autolite 3923 spark plugs 0.035 gap * 8mm Spark plug wires * 2,400-2,800 Stall converter * 1,500-6,500 dual plane intake * 80 GPH Fuel pump * 91 plus octane fuel * 680 cfm carburetor
Not Yet Reviewed
$4,790.99
Give new life to your ride with ATK High Performance GM 350 330 hp/380 lbs.-ft. Stage 3 long block crate engines. They are based on the tried-and-true small block Chevy and are built to perform right out of the box. ATK hand-assembles and balances each engine using top-quality parts to help them produce awesome power. Whether you are replacing an older, tired engine or just looking for a little more performance, ATK has you covered. Stage 3 long block crate engines include: * Handpicked, OE remanufactured blocks * ATK cast iron cylinder heads * 76cc combustion chambers * 165cc intake runners * 1.94 in./1.5 in. valves * ATK dual plane Intake manifold * OE crankshaft * OE 5.7 in. powder metal connecting rods * Hypereutectic flat-top pistons * Hydraulic flat tappet camshaft * .465 int./.488 exh. cam lift * 224 int./234 exh. cam duration at 0.50 * 9.1:1 compression * Distributor, spark plugs, and plug wires * Valve covers * Timing cover and double roller timing set * Oil pan, pump, and pickup tube * OE style long water pump * Balancer and 168 tooth flexplate
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$4,754.99
Bring your ride to life with ATK High Performance Ford 302 375 hp Stage 2 long block crate engines. These engines are based on the tried and true Ford 302 and are built to perform. ATK hand-assembles and balances each engine using top-quality parts to help them produce awesome power. Whether you are replacing an older, tired engine or just looking for a little more performance, ATK has you covered. Details and specs: * 375 hp/380 lbs.-ft. * Compression Ratio: 9.5:1 * ATK Aluminum heads * Hydraulic roller cam * Cast steel crankshaft 50oz external balance * Hypereutectic pistons * Seasoned OE roller block 1987-1995 * 4.040 in. bore x 3.000 in. stroke * One-piece rear main seal * Mechanical fuel pump provision * Dual sump oil pan HP08C, Front sump oil pan HP78C * Melling high volume oil pump * Double roller timing set * Left Hand inlet reverse rotation water pump (HP08C) * Right Hand inlet standard rotation water pump (HP78C) * 50oz external balancer * TCI 529610 157 tooth flexplate with 50oz balance * Edelbrock Performer RPM dual plane intake 7121 * Pro Billet distributor with melonite gear Cylinder Heads: * ATK aluminum cylinder heads * 58cc chamber * 2.02 in. intake/1.60 in. exhaust valves * 185cc intake runners * 1.6 aluminum roller rockers Roller Cam specs: * .512 intake/.512 exhaust * 220 intake/224 exhaust duration @ .050 - 112-degree lobe separation Recommended: * 34-36 degrees total timing * 13726548 firing order * Autolite 3923 spark plugs 0.035 gap * 8mm Spark plug wires * 680 cfm carburetor * Mechanical 80 GPH Fuel pump * 2,400-2,800 Stall converter * 91 plus octane fuel
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$5,866.99
ATK High Performance Ford 302 375 hp Stage 3 long block crate engines with EFI are designed to have great street manners and will work with most stock components. Teamed up with FiTech Self-Learning EFI systems, these ATK engines come complete from throttle body down to the oil pan. The only thing you will need is to supply is the fuel system--in line, in tank, or the FiTech Fuel Command Center. Plus, they are dyno-tested with your EFI system and ready to go! Details and specs: * 375 hp/380 lbs.-ft. * Compression Ratio: 9.5:1 * FiTech Go Street EFI (wire harness and handheld unit included) * ATK Aluminum heads * Hydraulic roller cam * Cast steel crankshaft 50oz external balance * Hypereutectic pistons * Seasoned OE roller block 1987-1995 * 4.040 in. bore x 3.000 in. stroke * One-piece rear main seal * Front sump oil pan * Melling high volume oil pump * Double roller timing set * Right Hand inlet standard rotation water pump * 50oz external balancer * TCI 529610 157 tooth flexplate with 50oz balance * Edelbrock Performer RPM dual plane intake 7121 * Pro Billet distributor with melonite gear (MSD ignition box required for tach signal) * Autolite 3923 spark plugs 0.035 gap * 8mm Spark plug wires Cylinder Heads: * ATK aluminum cylinder heads * 58cc chamber * 2.02 in. intake/1.60 in. exhaust valves * 185cc intake runners * 1.6 aluminum roller rockers Roller Cam specs: * .512 intake/.512 exhaust * 220 intake/224 exhaust duration @ .050 - 112-degree lobe separation Recommended: * 2,400-2,800 Stall converter * 34-36 degrees total timing * 13726548 firing order * 91 plus octane fuel
Not Yet Reviewed
$7,284.99
Bring your ride to life with ATK High Performance Ford 302 370 hp Stage 3 long block crate engines. These engines are based on the tried and true Ford 302 and are built to perform. ATK hand-assembles and balances each engine using top-quality parts to help them produce awesome power. Whether you are replacing an older, tired engine or just looking for a little more performance, ATK has you covered. Details and specs: * 375 hp/380 lbs.-ft. * Compression Ratio: 9.5:1 * ATK Aluminum heads * Hydraulic roller cam * Cast steel crankshaft 50oz external balance * Hypereutectic pistons * Seasoned OE roller block 1987-1995 * 4.040 in. bore x 3.000 in. stroke * One-piece rear main seal * Mechanical fuel pump provision * Dual sump oil pan HP08C, Front sump oil pan HP78C * Melling high volume oil pump * Double roller timing set * Left Hand inlet reverse rotation water pump (HP08C) * Right Hand inlet standard rotation water pump (HP78C) * 50oz external balancer * TCI 529610 157 tooth flexplate with 50oz balance * Edelbrock Performer RPM dual plane intake 7121 * Pro Billet distributor with melonite gear * Autolite 3923 spark plugs 0.035 gap * 8mm Spark plug wires * Quick Fuel 680 cfm carburetor with vacuum secondary's and electric choke * Mechanical 80 GPH Fuel pump Cylinder Heads: * ATK aluminum cylinder heads * 58cc chamber * 2.02 in. intake/1.60 in. exhaust valves * 185cc intake runners * 1.6 aluminum roller rockers Roller Cam specs: * .512 intake/.512 exhaust * 220 intake/224 exhaust duration @ .050 - 112-degree lobe separation Recommended: * 2,400-2,800 Stall converter * 34-36 degrees total timing * 13726548 firing order * 91 plus octane fuel
Not Yet Reviewed
$6,674.99
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