Zero to 60 Mph in 3.4 Seconds explains how the new Porsche 911 Turbo and Lotus Europa S get so much power out of “tiny” street-legal engines:
Drawing from engine designs and engineering know-how from the companies’ racing car divisions, the Lotus and Porsche engines largely owe their performance boosts to pressure chargers, as they have in years past. While Porsche calls it turbo technology and Lotus says ‘super charger,’ both systems serve to pump extra air into the engine.‘You have to think in terms of horsepower per liter,’ says Jamie Turner, chief engineer of powertrain Research for Lotus Engineering, which also offers engine design consulting services for major, yet undisclosed carmakers. ‘You really need to go to a pressure charging system to get (certain) levels of performance (in certain small engine sizes).’
But the aspirated engine designs are just a starting point. Porsche’s new 911 Turbo features what it calls variable turbine geometry, which allows the engine’s turbine to crank up more rapidly.
The system works by relying on a small turbo charger turbine, which revs up first during initial acceleration and is then replaced by a larger charger to deliver the requisite power for the Porsche’s 911 Turbo’s 480 horsepower engine.
‘Normally, when you push the throttle in with a big turbine, you can count one, two or three (seconds) and then the boost comes, but with this new turbine technology, you push the throttle in and you immediately have the response of the engine power,’ Durheimer said.
Why hadn’t anyone used this technology earlier?
This technology hasn’t been introduced in the automotive market in engines up until now due to the 1,000 degrees Celsius temperatures the turbine blades generate, Durheimer said.