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The 347-HP Audi SQ5 TDI uses electric turbocharging to eliminate lag

The performance SUV features a traditional turbo, an electric one and a mild-hybrid system.

Turbo lag? Never heard of it.

Audi

Engineers always want to keep turbo lag to a minimum in forced-induction engines, and Audi has a novel solution that uses electricity to tackle the problem. Like the earlier SQ7 TDI, Audi revealed Thursday that the SQ5 TDI will use an electric compressor to fight lag in the new performance crossover.

The SQ5's 3.0-liter diesel V6 engine has a traditional exhaust-driven turbocharger, but the electric compressor can kick in to provide some boost -- up to 20.4 psi of it -- at engine speeds below 1,650 rpm. Audi says that means "high torque is available immediately." Total output from the engine is rated at 347 horsepower and 516 pound-feet of torque.

The engine also has a mild-hybrid system, like many of Audi's newest cars. A 48-volt battery works with a special belt-alternator starter, which can improve stop-start performance. The SQ5 TDI can even coast with the engine off for up to 40 seconds at a time when the 48-volt battery is fully charged.

Being an Audi S model, the SQ5 TDI also has other sporty handling upgrades: torque vectoring and an optional sports rear differential for the Quattro all-wheel-drive system, a suspension that rides 1.2 inches lower than a standard SQ5, 20- or 21-inch wheels, adaptive dampers and enlarged brakes with 14.8-inch front discs.

Just like the Audi SQ7 TDI, which also uses an electric turbo to help quash lag, the SQ5 TDI is not coming to the US market. The highest-performing model we'll get here is the gasoline-fired SQ5, which boasts 354 hp from its 3.0-liter turbocharged V6 engine.