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There's a reason people like big, multi-cylinder engines and it isn't just about the noise they make or how much power they produce.
It's also to do with smoothness. And it's one reason some people are worried about the latest trend for downsized four-cylinder units, as they begin appearing in larger vehicles.
If Audi's next generation four-cylinders come to fruition, we may not have to worry.
The German firm has patented a four-cylinder engine which promises refinement and smoothness on-par with six and even eight-cylinder engines.
According to Autocar (via Motor Authority), the patent describes an "internal combustion engine with multi joint crank drive and additional masses on articulated connecting rods for damping free inertia forces."
Rather than pistons and connecting rods running in-line with the crankshaft, they're connected via a rocker link. A separate rocker link connects to different connecting rods, which act on a fixed shaft equipped with counterweights.
The idea is to separate the axis of the crankshaft from that of the pistons.
Audi's patent drawings do seem to illustrate one drawback--the engine seems almost as wide as a traditional V-shaped power unit.
However, space is not an issue in the kind of cars the engine would be aimed at: larger vehicles which typically use large six-cylinder and V-8 engines in the first place. Turbocharging would be used to make up the power deficit to larger units.
Multi-cylinder engines have long been valued for their smoothness, as well as their power and torque. More power pulses are delivered during each engine revolution, and each bank of cylinders typically balances the other.
Unfortunately, more cylinders means more friction in the engine, and that points the way to the latest trend for downsized four cylinders.
Ordinarily the lack of refinement would be detrimental to the sort of refinement that buyers of larger luxury or sports vehicles enjoy, but Audi's design could fix that in future--while improving fuel efficiency.