Although Ferrari is perhaps better known for its splendid-sounding V8 and V12 petrol engines, the sportscar marque isn’t entirely inexperienced with the humble four-pot, deploying a series of inline-four engines in some of its Formula race cars during the 1950s. Now, the automaker may be looking to get back into four-cylinder engines, as the automaker has filed a patent application with the European Patent Office for a four-cylinder engine design with a unique electric turbocharger system that could greatly enhance the exhaust note.
The patent application, which was uncovered by our friends at AutoGuide, describes how an electric turbine wheel placed within the four-cylinder’s exhaust duct could be finely-adjusted in real time to tune the exhaust note at any given engine speed. The wheel would act similarly to the internal valve(s) in any modern active exhaust system, Ferrari says, although rather than simply being a sort of “on/off” switch, the turbine wheel would allow for a full range of different tones.
In every other respect, the electric turbocharger system described by Ferrari’s patent application is much like those that have come before it, where an exhaust-driven turbine generates the electricity that drives a motor-driven compressor, with a battery serving as a reservoir of reserve energy. Such a setup can dramatically reduce turbo lag, thanks to the quick spool-up characteristics of the electric motor driving the compressor, and can help conserve fuel by, for instance, deactivating while the vehicle is at a steady cruising speed.
Using the electric turbo’s turbine wheel to tune the exhaust is a unique approach, and it could help Ferrari’s future forced-induction engines the sort of aural magnificence we’ve grown accustomed to – even with only four cylinders. Granted, using a computer control unit to slow the wheel down for the sake of delivering a more satisfactory exhaust note would run counter to efficiency, but as AutoGuide notes, performance needn’t suffer as the compressor will have plenty of battery reserve to pull from.
And of course, it’s worth saying that nothing precludes this system from being used on engines with greater than four cylinders, meaning the tech described in this patent application could help make the company’s V6s, V8s, and V12s of the future sound every bit as their normally-aspirated counterparts.