Car engines are getting smaller, but that doesn’t mean they’re getting less powerful.
Volvo has committed to using four-cylinder engines to increase efficiency, and the Swedish carmaker just unveiled a prototype 2.0-liter version that produces 450 horsepower, thanks in part to an electric turbocharger.
The engine is based on the Drive-E models launched earlier this year in various Volvo models, and is fitted with a turbo that uses a small electric motor, rather than exhaust gases, to drive a fan and pull more air into the combustion chambers.
Going electric eliminates “turbo lag,” the delay that’s caused when exhaust gases have to build up to the required pressure. That means more power with no waiting and, because the engine doesn’t need to rev to spool up the turbo, better fuel economy as well.
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The prototype Drive-E engine also features two conventional turbos, for a total of three. While Volvo didn’t say specifically, the electric turbo may only be used at low revs, with the other two taking over at higher speeds.
As more carmakers turn to downsized turbocharged engines, eliminating lag has become a major priority for engineers. The instant response of an electric turbo as seen as one promising solution.
The Volvo engine is currently just a prototype, but a production-ready version could definitely help the company in its downsizing mission.