Expansion intake manifold.
More power than a 911 Turbo – from the same flat-six engine. No, it wasn’t easy, which is why it required yet another worldwide innovation.

The air intake manifold on the new 911 GT2 employs a totally new principle unlike anything ever featured on existing induction systems. Our ‘expansion’ intake manifold is a radical new development that is the polar opposite of the resonance principle used on conventional turbocharged engines.

A resonance manifold increases engine output by forcing additional air into the combustion chambers. To do this, the manifold is designed in such a way that the air – which vibrates due to the action of the valves – is in a compression phase as it passes through the inlet ports. Unfortunately, compression not only increases air volume, it also increases air temperature. The result is poorer ignition.

Our new expansion manifold simply turns that principle around. The internal geometry is radically different from that on a resonance intake system. Key modifications include a longer distributor pipe, with a smaller diameter and shorter intake pipes.

As a result, the air is in the expansion phase as it enters the combustion chambers. Since expansion always cools, the air/fuel temperature is lower and ignition is significantly improved – thereby increasing performance. Of course, the amount of air that enters the engine under expansion is less than it would be under compression. To compensate for this, we’ve simply increased the boost pressure from the turbos by approximately 2.9pis. The resulting increase in temperature – again through compression – is immediately offset by the uprated intercoolers.

Instead of hot compressed air entering the combustion chambers, we now have cooler air generating more power and torque. The result: a major improvement in engine efficiency and therefore lower fuel consumption even under heavy loads and high rpm.

A simple solution, but then that’s often the way when take a new approach to old ideas.