2012 models of Chevy sports coupe and convertible get more performance from V6 and tweaked suspension option for SS.

Chevrolet launches its 45th Anniversary Special Edition Camaro this summer on both V6 and V8 models with a special paint treatment, wheels and interiors , while V6 models across the board get a boost in horsepower and the SS receives a new FE4 performance suspension package.

The anniversary models include all optional upgrades for 2012, Chevy said, with unique design features for the body and interior.

Along with its anniversary, Chevrolet is also celebrating Camaro’s ascendancy over arch-rival Ford Mustang in 2010 sales.

“The appeal of Camaro design and performance has powered it to the top of its segment,” said Rick Scheidt, vice president of Chevrolet marketing. “For 2012, we’re capitalizing on that momentum with enhancements to Camaro’s performance and comfort.”

Chevy also is unveiling the the high-performance Camaro ZL1 for 2012, which the GM division calls “the most technologically advanced car ever developed in its segment.”

An 11 horsepower increase to 323 horsepower will be delivered by the new 3.6L direct-injection V-6, the LFX engine, the automaker said, with no fuel-mileage penalty. Among the improvements to the new engine are:

• New cylinder head design with integrated exhaust manifold.
• Improved intake port design and larger intake valves within the cylinder heads.
• Longer-duration intake camshafts.
• Composite intake manifold.
• New fuel pump and isolated fuel rail.
• New, optimized-flow fuel injectors.
• Structural front cover and cylinder block enhancements.
• Stronger and lighter-weight connecting rods.
• Camshaft cap and throttle body design enhancements.