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The new Audi S4 reverses the carmaker's long-time policy of installing bigger engines with each new generation - it gets a 3-litre V6 in place of a 4.2-litre V8.
But a supercharger will compensate for the S4's drop in capacity, boosting engine power to 250kW, only about 5kW short of the V8's output. Even more impressive is the increase in torque, from 409Nm to 439Nm.
What really stands out though is the claimed fuel economy from the direct-injection engine.
The current S4 returns around 13.5 litres/100km (21mpg) - but the newer and lighter V6 is good for 9.7 litres/100km, or 29mpg, says Audi. That's an improvement of 26 per cent.
The new powerplant not only outperforms its V8 predecessor, but does so with a 30 per cent reduction in CO2 emissions.
Both the sedan and Avant estate will be unveiled at the Paris Motor Show tomorrow and go on sale in New Zealand next year.
The S4's V6 shares its componentry with the six engines in the Audi range, combining single turbocharging with FSI direct injection. But the newcomer uses an alternative method of forced induction - a compact supercharger chosen because it delivers keener response than even two turbo chargers could achieve.
The supercharger's compact dimensions enable it to fit easily inside the 90-degree V of the cylinder banks and, as a result, the gas paths to the cylinder are extremely short, resulting in throttle response that even a naturally aspirated engine of the same displacement can't match.
With the help of compressors, the new unit develops its peak torque from 2500rpm right through to 4850rpm, enabling a zero to 100km/h sprint time of just over five seconds for the manual sedan and estate and an electronically limited top speed of 250km/h.
Buyers will get a choice of a six-speed manual gearbox or an optional seven-speed twin-clutch S-tronic transmission with gear-changing paddles behind the steering wheel.
In terms of styling, the S4 builds on the strong design of the latest A4. Subtle changes include side skirts and badging, as well as aluminium-effect wing mirrors.
At the back, quad exhaust pipes hint at the extra muscle the newcomer delivers over the current range-topping A4 3.2-litre Quattro.
As with that model, the all-wheel-drive system sends 60 per cent of power to the back tyres. It works with a new active sport differential, which directs drive to the outer rear wheel in bends to give more grip and stronger acceleration.
The S4's suspension is stiffer than standard cars and it sits 20mm closer to the road for better handling. As is standard, owners get 18-inch alloys with 19-inch rims as an optional extra.
Audi's Drive Select system is fitted, too. This gives a choice of comfort, auto or dynamic modes and alters the throttle response, the steering weight and the S-tronic box's shift points to suit the driver's tastes.
Further adjustment is offered by adaptive shock absorbers, although this isn't the clever magnetic system found on the R8. Instead, simpler hydraulic valves switch to a sportier set-up, as they do on the new VW Scirocco. These can be monitored via the optional MMI cabin control system.
Inside, the figure-hugging sports seats come with electric lumbar support, while options include a high-end Bang and Olufsen stereo, sat-nav and adaptive cruise control.
