Infiniti further teases a high-performance version of its Q50 sedan today at the Geneva auto show by borrowing an engine from sister-brand Nissan for its Eau Rouge concept.

The Eau Rouge debuted at January’s North American International Auto Show in Detroit sans powertrain, but in Geneva the car snags the 3.8L twin-turbo V-6 from Nissan’s GT-R sports car.

“Building on the extremely positive feedback on the Q50 Eau Rouge at its recent Detroit auto show launch, we decided to further whet the appetite of performance sports sedan fans by engineering this powerful heart into our blood-red beast,” Johan de Nysschen, president-Infiniti, says in a statement.

In the Infiniti concept, the 3.8L is estimated to make 560 hp, up from 545 hp in the ’15 GT-R in the U.S. Nissan’s luxury brand pairs the 24-valve V-6, also making 443 lb.-ft. (600 Nm) of torque, with a 7-speed gearbox and all-wheel drive.

Infiniti pegs the Eau Rouge’s top speed at nearly 180 mph (290 km/h) and 0-60 mph (97 km/h) time at less than four seconds.

While Infiniti has stated its desire to build the Eau Rouge, it still won’t officially confirm production.

In January, de Nysschen told media in Detroit he “absolutely insists” on the concept making it to production, but the brand still was wavering over what engine to use. The existing 5.6L V-8 from the M sedan was then a possibility as well as the GT-R’s mill.

De Nysschen also has been an advocate of downsized engines, so it’s no surprise Infiniti uses its Geneva stage to announce arrival dates for the Q50’s 2.0L turbocharged 4-cyl., making 211 hp and 236 lb.-ft. (320 Nm) of torque.

While Infiniti doesn’t say so in its pre-show release, this is likely joint-venture partner Daimler’s direct-injected engine, which Nissan is to begin building at its Decherd, TN, plant in 2015 for both Infiniti and Daimler’s Mercedes-Benz.

The 2.0L will arrive first in the Q50 in China this spring, launch in Europe this fall and be available in the remainder of Infiniti’s global markets by year-end.

“It’s very clear that in that particular market segment the action today is in the 4-cyl. category,” de Nysschen told WardsAuto in August, adding Infiniti’s decision to keep the G37 sedan in its U.S. lineup was so the Q50 “does not become a victim of the fact that the current entry engine is a 328-hp V-6.”

cschweinsberg@wardsauto.com