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ATK LM7-LB-2 Chevy LM7/LS1 347CI Base Engine 500HP

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#35020086

ATK LM7-LB-2 Chevy LM7/LS1 347CI Base Engine 500HP

Oil: Conventional / Non Synthetic 10W30
Oil Filter: Wix or K&N per application
Timing: 34-36 Degrees

$7,716.99

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Product Summary

Long Block Crate Engine Type, 10.3:1 Compression Ratio

Oil: Conventional / Non Synthetic 10W30
Oil Filter: Wix or K&N per application
Timing: 34-36 Degrees
Spark Plug Gap: .035”

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Key Specs

Crate Engine Type	Long Block
Compression Ratio	10.3:1
Engine Displacement	347 cu. in.
Camshaft Type	Hydraulic Roller
Cylinder Head Material	Aluminum

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ATK Engines LM7-LB-2 Details

This is an LM7 (Iron LS1/LS6) based engine with CNC Ported Cathedral Port Aluminum heads making a very streetable 500HP+. Expect big mid to upper end power, will have a noticeable idle. For optimal Performance you will need headers, chassis dyno tune and 36lb injectors. Your engine may not necessarily come with all components listed, but they are listed as our recommendations of parts to run for optimal performance.

Engine Specifications:

HP: 500

TQ: 450

Block: OE LM7 5.3L Gen III

Bore/Stroke: 3.903” x 3.622”

Displacement (cu.in): 347

Crankshaft: OEM GM 24 tooth reluctor wheel

Rods: Scat 4340 forged I beam 6.125” with ARP 8740 bolts

Pistons: Wiseco forged 10.3:1 compression

Rings: Moly

Camshaft: Hyd. Roller

Cam Specs: 228/234 @50 .604/.609 112LSA

Timing Chain: Billet HD .250” roller

Cylinder Heads: CNC ported cathedral port cores 2.02/1.60 valves, dual springs, titanium retainers

Rocker Arms: OE 1.7 ratio

Oil Pump: Melling

Recommended Components:

Flexplate/Flywheel: Stock internally balanced

Balancer: Stock internally balanced/per application

Intake Manifold: Stock/Aftermarket EFI intake or Carbureted setup

Water Pump: Per application

Fuel Pump: Electric per application

Fuel Injectors: 36lb injectors

Spark Plugs: NGK #3186

Spark Plug Wires: Factory

Engine Info:

Oil: Conventional / Non Synthetic 10W30

Oil Filter: Wix or K and N

Timing: Set to factory specifications via PCM module (ECM TUNING REQUIRED).

Spark Plug Gap: .040”

Firing Order: 18726543

Octane: 91+

Stall Converter: 2200-2500

Exhaust: 1 5/8 + Headers

Notes: This engine can replace the 1999-2007 Chevy 5.3L LM7 engine with supporting modifications or any other factory LS equipped vehicle. It can also be retrofitted for aftermarket EFI/Carb setups. ECM MUST BE TUNED, not doing so can damage the engine. : A PCV valve must be ran; please follow the valve cover instructions provided. You must also run an Air-Oil separator system such as the Moroso #85487 to capture the excess crankcase vapors LS engines are known for. If you are not running a MAP Sensor, the MAP timing option in the timing control box must be zeroed out all the way across. Failure to do so will allow the controller to add timing which can lead to detonation. You must also run some sort of a steam line kit that dumps to your water pump, radiator or radiator hose; we recommend a 4 corner setup like the Trick Flow #TFS-306SB601. This allows air pockets/hot spots to escape the heads and can also be used to purge out trapped air when filling the radiator for the first time.

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 in their application. Some modifications to the vehicle may be required using these and or other aftermarket parts. . ATK reserves the right to substitute parts used in engines if necessary.

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Warranty (ATK Engines)

Technical Information (ATK Engines)

CARB Warning

Follow EPA, CARB, and state regulations for engine changes

Emissions warning: this part is for vehicle engine changes, not direct oem engine replacements. In California, engine changes are legal when done in compliance with California bureau of automotive repairs (bar) engine change policy. For assistance, call bar referee at: (800) 622-7733. And see https://bar.Ca.Gov/consumer/smog_check_program/engine_changes. All customers must comply with federal epa mobile source enforcement memorandum no. 1a (and addendum) and all applicable state regulations when conducting engine changes. Improper installation and/or use of this part in California may subject the installer and/or owner to a $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering. There are similar restrictions and penalties under federal law and laws of all states for use of this engine change part on makes or models of vehicles that render them noncompliant with applicable state and/or federal emission laws with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine

CA WARNING:

Can expose you to lead, a carcinogen and reproductive toxicant. See www.P65Warnings.ca.gov

CARB warning

ATK Engines LM7-LB-2 Specifications

KEY SPECS
MFG. Part #	LM7-LB-2
Brand	ATK Engines
Crate Engine Type	Long Block
Compression Ratio	10.3:1
Engine Displacement	347 cu. in.
Camshaft Type	Hydraulic Roller
Cylinder Head Material	Aluminum
Piston Material	Forged Aluminum
Carburetor Included	No
Intake Manifold Included	No
Distributor Included	No
Valve Covers Included	Yes
Cylinder Heads Included	Yes
Throttle Body Included	No
Timing Cover Included	No
Oil Pan Included	No
Water Pump Included	Yes
Harmonic Balancer Included	No
Flexplate Included	No
Flywheel Included	No
Air Cleaner Included	No
Spark Plugs Included	No
Spark Plug Wires Included	No
Computer Included	No
Wiring Harness Included	No
Reluctor Wheel	24x

GENERAL
Bore x Stroke (in)	3.903" x 3.622"
Material Type	Iron
Sold in Quantity	Each

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