GM 6.2 Liter V8 Supercharged LS9 Engine
The 6.2-liter V8 Supercharged LS9 is an engine produced by General Motors for use in high-performance vehicles. Being one of a handful of GM engines assembled by hand, the LS9 is part of GM’s 4th-generation V8 Small Block engine family and is notorious for being the automaker’s most powerful production engine. It was produced for the sixth-generation Corvette ZR1 — the flagship of the Corvette lineup.
The supercharged LS9 is the most powerful production engine GM has ever offered. It is the standard engine in the Corvette ZR1 and helps it achieve enviable performance benchmarks. It is civil at low speeds and remarkably tractable at all speeds. Percolating beneath the civil demeanor, however, is a deep well of power. An advanced, Gen IV supercharger with a unique four-lobe rotor design helps the LS9 produce its admirable, broad performance range.
The LS9 is assembled by hand by a single builder at GM’s unique Performance Build Center in Wixom, Mich. The 100,000-square-foot facility weaves the best practices of low-volume niche manufacturers and the established quality and manufacturing standards at GM to ensure the highest-quality specialized engines.
- Enhanced Cylinder Block: The 6.2L engine block used with the LS9 is cast from 319-T7 aluminum and fitted with cast-iron cylinder liners. It has been strengthened 20 percent compared to prior generations of this engine, by optimizing the size of the bulkhead “windows” to take advantage of material thickness in the bulkhead. The enlarged bulkhead windows also improve bay-to-bay breathing by managing airflow inside the engine more efficiently, thereby decreasing pumping loss, or reducing resistance to the pistons’ downward movement. The engine block was developed with the latest math-based tools and data acquired in GM’s racing programs, and it provides an exceptionally light, rigid foundation for an impressively smooth cam-in-block engine. Its deep-skirt design helps maximize strength and minimize vibration, and its aluminum construction reduces weight approximately 100 pounds compared to a conventional cast-iron cylinder block.
- Deck Plate Honing: A precision machining process typically reserved for high-performance engines, is used on the LS9 cylinder block to maximize engine life, reduce friction between engine parts and increase horsepower. It is advantageous in applications where cylinder head pressures are greater than average – such as with a supercharged engine – to ensure cylinder sealing and prevent scuffing of the piston against the bore wall. In the LS9 engine, this means improved bore life and ring sealing. True bores and better sealing are keys to optimizing power.
- Forged-Aluminum Pistons with Oil-Spray Cooling: The LS9’s pistons are premium forged aluminum components, for a high-performance combination of low mass, high strength and durability. These are considerably lighter than conventional aluminum pistons, which translates to less reciprocating mass inside the engine. The LS9 also incorporates oil-spray piston cooling. Eight oil-squirting jets in the engine block drench the underside of each piston and the surrounding cylinder wall with an extra layer of cooling, friction-reducing oil. The oil spray reduces piston temperature, promoting extreme output and long-term durability.
- Lightweight Rotating Assembly with Titanium Connecting Rods: Within the LS9’s cylinder block spins a balanced, dropped-forged micro-alloy steel crankshaft with a nine-bolt flange to mount the flywheel. Titanium connecting rods mate the crank with the pistons, for the ultimate combination of strength and light weight. The titanium rods weigh roughly 25 percent less than conventional iron or steel. They reduce pressure on both the rod-end bearings and main bearings, and allow the bearings to be optimally sized for the least amount of friction.
- Refined Low-Overlap Camshaft: A refined camshaft helps balance the 6.2L LS9’s remarkable output with silky, tractable low-rev operation. It camshaft operates the engine’s valves and its design is crucial to both power and smoothness.
- High-Flow Rotocast Cylinder Heads: The LS9 cylinder heads are manufactured with a unique rotocast method, which rotates the head mold as the molten alloy cools and essentially eliminates porosity, or microscopic pockets of air trapped in the casting. Rotocasting delivers a stronger part that helps maintain performance and structural integrity over the life of the engine.
- Dual-Pressure/Center-Feed Fuel System: To ensure appropriate fueling in all conditions, the LS9 features a dual-pressure fuel system. It delivers about 36 psi (250 kPa) at idle and low speeds. Yet the electronic throttle management system can immediately increase fuel pressure to 87 psi (600 kPa) for sustained high-speed operation or wide-open throttle. The dual-pressure system reacts according to throttle application, and presents several advantages. It limits the energy used by the fuel pump at low speeds, for maximum efficiency, and it reduces operational noise. The LS9 also employs a center-feed fuel rail that delivers gasoline to the center of the injector rail and each bank. This helps reduce fuel pressure variation among the injectors, as well as noise.
- Direct-Mount Ignition Coils: The LS9’s coil-on-plug ignition features advanced coils that are smaller and lighter than those used on previous V8s. An individual coil for each spark plug delivers maximum voltage and consistent spark density, with no variation between cylinders.
- Supercharger with Four-Lobe Rotors: State-of-the-art supercharging technology is the foundation of the LS9’s remarkable performance. The supercharger is an air pump driven by the engine’s crankshaft. It forces more air into the engine’s combustion chambers than the engine could otherwise draw on its own. The increased volume of oxygen allows the engine to efficiently process more fuel, and thus generate more power.
- Dual-Brick Air-to-Liquid Intercooler: An advanced intercooling system increases the 6.2L LS9’s performance and extends its supercharger’s benefits. The engine’s charge cooler is integrated in the supercharger case just above the rotors, with two air-to-liquid cooling “bricks” that substantially lower the temperature of air used in the combustion process. Intercoolers are familiar features on supercharged and turbocharged engines. Similar in concept to an engine’s radiator, intercoolers cool the air pumped by the charging device into the cylinders. Cooler air is denser air, which means more oxygen in a given volume, resulting in optimal combustion and more power. Traditionally, intercoolers look like small radiators mounted somewhere outside the engine, with air fed into the engine through a plumbing network.
- Dry Sump-Style Oiling System: To ensure the 6.2L LS9 operates at peak, low-friction efficiency, and to promote durability during extended high-rpm use under high cornering loads, the engine is equipped with a racing-style dry sump-type lubrication system and dual-gerotor oil pump.
- Stainless Steel Exhaust Manifolds with Close-Coupled Catalysts: The 6.2L LS9 exhaust manifolds are constructed of stainless steel and designed on the principle that low restriction and less pumping loss equals more horsepower and torque. Each manifold consists of four tubes hydroformed from 309 stainless steel. The manifolds are fitted with a pair of close-coupled catalytic converters that heat quickly, achieving light-off temperature and closed-loop operations in seconds.
- Advanced Electronic Throttle Control: With ETC, there is no mechanical link between the accelerator pedal and the throttle body. A sensor at the pedal measures pedal angle and sends a signal to the engine control module (ECM), which in turn directs an electric motor to open the throttle at the appropriate rate and angle. The ETC system can deliver outstanding throttle response and greater reliability than a mechanical connection.
- 58X Ignition System: The LS9 has an advanced 58X crankshaft position encoder to ensure that ignition timing is accurate throughout its operating range. The new 58X crankshaft ring and sensor provide more immediate, accurate information on the crankshaft’s position during rotation. This allows the engine control module to adjust ignition timing with greater precision, which optimizes performance and economy. Engine starting is also more consistent in all operating conditions.
|Type:||6.2L Gen IV V8 Small Block|
|Displacement:||6162 cc (376 ci)|
|Valve configuration:||Overhead valves (2 valves per cylinder)|
|Assembly site:||Wixom, Michigan|
|Valve lifters:||Hydraulic roller|
|Firing order:||1 – 8 – 7 – 2 – 6 – 5 – 4 – 3|
|Bore x stroke:||103.25 x 92mm|
|Fuel system:||Sequential fuel injection|
|Fuel Type:||Premium required|
|Maximum Engine Speed:||6600 RPM|
|Positive crankcase ventilation|
|Valves per cylinder:||2|
|Bore Center (mm):||111.76|
|Horsepower hp (kw)|
|Chevrolet Corvette ZR1:||638 hp (476 kW) @ 6500rpm SAE CERTIFIED|
|Torque: lb-ft (Nm)|
|Chevrolet Corvette ZR1:||604 lb-ft (819 Nm) @ 3800 rpm SAE CERTIFIED|
|Cylinder head:||A356-T6 rotocast cast aluminum|
|Intake manifold:||Cast aluminum|
|Exhaust manifold:||Stainless steel|
|Main bearing caps:||Forged steel|
|Connecting rods:||Forged Titanium|
|2.3 L/rev Supercharger|
|Integrated dual coolant to air intercooler|
|Titanium inlet valve|
|Piston oil spray cooling|
|Hollow steel exhaust valve|
|Direct mount ignition coils|
|Chevrolet Corvette ZR1 (Discontinued)||MH3-6L95M|
|Chevrolet Corvette ZR1 (Discontinued)||ME2-6L95M|