Audi reveals a new turbo engine for Euro-spec A5 coupe

Audi is putting a new engine in the sleek A5 coupe, targeting better fuel economy. As of now, though, it's not scheduled for the United States.

The turbocharged four-cylinder unit will displace 1.8 liters and deliver 170 hp. Peak torque is 236 lb-ft and arrives between 1,400 rpm and 3,700 rpm. The current 2.0-liter four-cylinder makes 211 hp and 258 lb-ft of twist.

The new powerplant will push the A5 from 0 to 62 mph in 7.9 seconds, on its way to a top speed of 143 mph.

The turbocharger is a new design that develops a boost pressure of up to 19 psi. The turbine is made from a new alloy that can handle 1,796 degrees Fahrenheit without deforming. Boost pressure is electronically controlled precisely to reduce fuel consumption.

Efficiency is the goal of the new engine. Audi says consumption has been improved by 21 percent. The engine will use 5.7 liters per 100 kilometers, which converts to about 41 mpg. The engine also puts out fewer emissions than its predecessor.

Engine weight has been reduced by about eight pounds with a new casting process for the crankcase that reduces wall thickness. Internal friction was also reduced by a new coating on the piston skirts.

The engine puts Audi ahead of the Euro 6 regulations for emissions, which do not go into effect until 2015.

We'd guess the new powerplant eventually will come stateside, and the smart money says it will trickle down to the A4 and the A3 as well.

By Jake Lingeman