This is a case of addition by subtraction.  We all know that a reduction in mass allows for increased fuel economy and contributes to more nimble handling characteristics. The highly versatile 3.6 liter, direct-injected, variable-cam-timed V6 engine, which General Motors employs in a variety of applications, was put on a diet and given a little reconstructive surgery for Camaro duty.

By eliminating the cast iron exhaust manifolds, gaskets, heat shields, and mounting hardware of the “old” 3.6L DI engine, the engineers at GM were able to shave a whopping 13 pounds off the nose of the 2LS Camaro and increase fuel economy to 30 MPG for 2012.

In order to accomplish this incredible feat, the exhaust manifold and the cylinder head had to be combined into one aluminum unit.

By utilizing Computer Aided Design (CAD) software, the engineers were able to construct and test their new design in virtual reality. Once the design had been optimized for cylinder to cylinder balance and airflow in theoretical manipulations, physical prototypes were validated on airflow benches.

So, what are the results?  By enlarging the intake valves by 1.4 mm, intake airflow is increased by 7%. This, by and large, is responsible for the 11 horsepower bump to 323. Exhaust flow is also up 10%. Due to the change in exhaust scavenging, the catalytic converters are closer to the exhaust point, beginning the emissions reduction process sooner and contributing to reduced emissions. Not to be discounted as advantages, the new head design decreases the overall width of the engine by an extraordinary 4.6 inches and, finally, the acoustic properties of the new design help to achieve a 1 decibel reduction in engine noise at idle.