LS6
The LS6 is a high-performance 5.7-liter (346 cubic inch) V8 engine developed by General Motors as part of its Generation III LS small-block engine family, produced from 2001 to 2005 exclusively for premium performance vehicles.[1] It features an all-aluminum block with cast-iron cylinder liners, a bore of 3.90 inches and stroke of 3.62 inches, and a compression ratio of 10.5:1, delivering output of 385 horsepower at 6,000 rpm and 385 lb-ft of torque at 4,800 rpm in its initial 2001 version, increasing to 405 horsepower and 400 lb-ft in the 2002–2004 Corvette Z06, and 400 horsepower and 395 lb-ft in the 2004–2005 CTS-V.[2] Designed as an evolution of the LS1 engine, the LS6 incorporates enhancements like revised cylinder heads (casting #243) with 50.8 mm (2.00 in) intake valves and sodium-filled 39.4 mm (1.55 in) exhaust valves for improved flow and heat dissipation, more aggressive camshafts with lifts increasing from 0.525 inches (both) in 2001 to 0.551-inch intake and 0.547-inch exhaust in 2002-2004, and a higher-flowing intake manifold to achieve superior power density.[3] Introduced in the 2001 Chevrolet Corvette C5 Z06 as a high-performance variant, the LS6 enabled a 0-60 mph acceleration time of approximately 4.0 seconds and a top speed exceeding 170 mph, establishing the Z06 as a benchmark for naturally aspirated sports cars of the era.[1] Production continued through the 2004 model year for the Corvette Z06, with the engine's final application in the 2004–2005 Cadillac CTS-V sedan, where it provided rear-wheel-drive performance with a 0-60 mph time around 4.6 seconds.[4] Assembled at GM's St. Catharines plant in Ontario, Canada, the LS6 was succeeded by the 6.0-liter LS2 in 2005, but its compact design, rev limit of 6,500 rpm, and six-bolt main bearing caps made it a favorite among enthusiasts for engine swaps and modifications due to its balance of power, reliability, and aftermarket support.[1]Overview
Introduction
The LS6 is a 5.7 L (346 cu in) naturally aspirated V8 engine from General Motors' Generation III small-block family, produced from 2001 to 2005.[1][4] As a high-performance variant, it was engineered specifically to provide superior power compared to the standard LS1 engine.[1] Introduced as part of General Motors' initiative to achieve elevated performance levels in production vehicles, the LS6 represented an advancement in aluminum small-block design while retaining pushrod architecture.[3] This engine marked a significant evolution in GM's compact V8 lineup, emphasizing lightweight construction and efficient power delivery.[3] The LS6 features a displacement derived from a bore of 99 mm (3.90 in) and a stroke of 92 mm (3.62 in), resulting in a total capacity of 5,665 cc.[1][3] Its basic architecture consists of a 90-degree V8 configuration with an aluminum block and heads, electronic fuel injection, and sequential ignition.[1][4]Key specifications
The LS6 is a naturally aspirated, overhead valve (OHV) pushrod V8 engine.[1] It features an aluminum cylinder block with a deep-skirt design and aluminum cylinder heads.[1][5] The valvetrain consists of 2 valves per cylinder actuated via hydraulic roller lifters and pushrods from the camshaft located in the block.[1][2] The fuel system employs sequential multi-port fuel injection with 30 lb/hr injectors.[5][1] The compression ratio is 10.5:1 across production years.[1][2] The engine has a redline of 6,500 rpm.[1] The firing order is 1-8-7-2-6-5-4-3.[1]| Specification | Details |
|---|---|
| Engine type | Naturally aspirated OHV pushrod V8[1] |
| Block material | Aluminum, deep-skirt design[5] |
| Head material | Aluminum[1] |
| Valvetrain | 2 valves/cylinder, hydraulic roller lifters, pushrods[1] |
| Fuel system | Sequential multi-port injection, 30 lb/hr injectors[5] |
| Compression ratio | 10.5:1[1] |
| Redline | 6,500 rpm[1] |
| Firing order | 1-8-7-2-6-5-4-3[1] |