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http://www.gm.com/company/racing/technology/IndyV8.htm

Louis Chevrolet, co-founder and namesake of the Chevrolet Motor Division, was a gifted engineer and a daring race car driver. He competed in the Indianapolis 500 four times, with a best finish of seventh in 1919. His brother Gaston won the Indy 500 in 1920.

The Chevrolet name returned to the open-wheel arena in 2002, borne by a purebred competition engine that incorporates advanced, yet affordable, technology. Unlike the ungainly engines of Louis Chevrolet's day, the new Chevy Indy V-8 racing engine is a sophisticated, technically advanced powerplant.

GM Racing, the technical arm of GM's motorsports program, designed and developed the major components of the new Chevy Indy V-8 in house using GM personnel and GM's technical resources. The engine block, sump, cylinder heads, cam covers, and front cover carry factory part numbers, and are distributed through selected engine builders.

The 2003 Chevy Indy V-8 is the second new Indy car engine produced by GM Racing in two years. It is the successor to the Chevrolet engines that won 14 IRL events in 2002 and captured the manufacturers', drivers' and team championships. The 2003 Chevy Indy V-8 is 3 inches narrower, 3 inches shorter and 35 pounds lighter than the 2002 version. The 3.5-liter (214 ci) engine has an aluminum cylinder case, aluminum cylinder heads with four valves per cylinder, dual overhead camshafts and sequential electronic fuel injection. It produces more than 675 horsepower and weighs 280 pounds.

"The Chevy Indy V-8 engine program reflects the values that have made Chevrolet America's brand," Negri continued. "We will be responsive to the needs of our customers and flexible in our dealings with teams. Our goal is to create an engine program that is straightforward, fair and user-friendly. We will sell Chevy Indy V-8 engines to IRL teams at the IRL-specified price of $120,000, and we will institute a leasing program if requested by our customers. Most importantly, we are committed to the principle of accessible and affordable technology. Updates to the Chevrolet engine package will be released to all bona fide Chevy teams when the equipment is validated and manufactured in sufficient quantities."

GM Racing engineers used powerful design tools to create the new engine, which went from concept to the dyno cell in just nine months.

"The 2003 Chevy Indy V-8 builds on the experience GM Racing has gained with two previous IRL engines," said lead engine designer Roger Allen. "It also takes full advantage of changes in the technical regulations as the IRL series has moved from production-based engines to purpose-built racing engines. For example, the new Chevy Indy V-8 has a precision gear camshaft drive instead of chains, two fuel injectors per cylinder instead of one, and removable light-alloy wet cylinder liners instead of the cast-iron dry liners that were used previously."

"In addition to this new hardware, GM Racing is also developing a new engine management system with sophisticated software features," Allen added. "Prototype units have already been tested extensively under racing conditions, and GM Racing's electronics specialists are tailoring the system to the requirements of the new engine."

The IRL engine rules for 2003 specify a maximum engine displacement of 3.5 liters (214 cubic inches). Engine speed is regulated by a programmable rev limiter to a maximum of 10,300 rpm (a 400 rpm reduction from the 10,700 rpm maximum in 2002) and 180-degree "flat" crankshafts are required.

The nature of Indy car racing makes unique demands on an engine, including the use of methanol fuel, sustained high-speed operation and installation as a fully stressed chassis member. The Chevy Indy V-8 was designed to meet these requirements.

The IRL engine formula also presents stringent technical challenges. The IRL rules stipulate a maximum cylinder bore diameter of 93 mm (3.66 inches), which requires a 64.4 mm (2.53-inch) stroke crankshaft to produce 3.5 liters of piston displacement. This stroke yields a mean piston velocity of 4,385 feet per minute and a maximum acceleration approaching 7,000 times the force of gravity at 10,300 rpm. This piston acceleration requires special attention to piston, pin, pin lock, and connecting rod design to ensure reliability in a 500-mile race.

The Chevy Indy V-8 block has light-alloy wet cylinder liners. The sump has five integral main bearing supports and provisions to scavenge oil from the crankcase. The engine is a dry deck design that uses cylinder sealing rings and O-rings between the block and cylinder heads, instead of conventional head gaskets.

Peak power is all-important on the high-speed ovals where the IRL series competes. The need to maximize power at the 10,300-rpm limit defined the Chevy Indy V-8's camshaft timing, valve sizes, and port volumes. The Chevy Indy V-8's aluminum alloy cylinder heads are CNC-machined. Four camshafts operate the 32 titanium valves directly through inverted-bucket lifters. Conventional dual-coil steel springs close the valves. (Pneumatically operated valvetrains are prohibited.)

The electronically controlled coil-at-plug ignition system has no moving parts. This design provides maximum energy to the spark plugs and eliminates the need for a conventional distributor and spark plug wires.

Maximum engine speed is regulated in the IRL series by a tamperproof electronic rev limiter that is maintained and programmed by IRL technical inspectors. The rev limiter is a cornerstone of the IRL's commitment to contain costs and maintain safe racing speeds.

"In order to achieve a competitive advantage in the IRL series, an engine manufacturer has to focus on fundamentals such as improving efficiency and minimizing parasitic power losses," Negri noted. "These are topics that have relevance to production engines."

Louis Chevrolet would no doubt approve
 
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