Engine Specifications

This is an LM7-based engine with CNC ported cathedral port aluminum heads making a very street-able 540hp. Expect big mid to upper power, which will have a noticeable idle. For optimal performance, you will need headers, chassis dyno tune, and upgraded injectors.

• Horsepower: 540 hp
• Torque: 505 lb/ft

Block Information:

• OE LM7/5.3L iron
• Bore/Stroke: 3.903" x 4.000"
• Displacement: 383ci

Rotating Assembly:

• Crankshaft: K1 4340 forged 24 tooth reluctor wheel
• Rods: K1 4340 forged I beam 6.125" with ARP 8740 bolts
• Compression Ratio: 10.6:1
• Pistons: Wiseco forged
• Rings: Moly

Camshaft Specs:

• Camshaft: Hydraulic roller
• Cam Duration @ .050": Intake 228 / Exhaust 234
• Cam Lift: Intake .604" / Exhaust .609"
• Lobe Separation Angle: 112lsa

Cylinder Head Information:

• Cylinder Heads: OE aluminum CNC ported cathedral port, dual valve springs, and titanium retainers
• Valve Size: 2.02" Intake / 1.60" Exhaust
• Rocker Arms: OE 1.7 ratio
• Timing Chain: Billet HD .250" roller

Oil Pump Information:

• Oil Pump: Melling 

 Base Engine Includes:

• Short Block
• Camshaft
• Timing Set
• Cylinder Heads
• Oil Pump 

Recommended Components

• Balancer: Stock internal balance/per application
• Intake Manifold: Stock EFI, aftermarket EFI, or carbureted  intake
• Flexplate/Flywheel: Stock internal balance
• Fuel Pump: Electric per application
• Fuel Injectors: 36lb injectors
• Spark Plugs: NGK #739-TR5GP
• Spark Plug Wires: Factory
• Water Pump: Per application

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 an aftermarket EFI/Carb setup. ECM must be tuned, not doing so can damage the engine.

Disclaimer: Power figures can vary based on parts used by the end user. Some modifications to the vehicle may be required using these and or other aftermarket parts.

Engine Break-In Procedure

Use conventional or break-in oil (non-synthetic) for the first 600 miles of operation. Do not drive for long periods at any single speed, always vary your speed. Do not tow a trailer or put other heavy loads on the vehicle. Check the engine oil and coolant levels daily. 

At 600 Miles change the engine oil and filter using conventional (non-synthetic) oil. Check fuel and ignition settings; adjust valves (where applicable).

After the first 5,000 of service synthetic engine oil may be used. Follow your vehicle owner’s manual for service intervals.

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.

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