Europe's stringent emission laws have forced some shuffling deep within some of the continent's biggest automakers, a lot of whom have had to make sacrifices on killing off their eight-cylinder engines in favor of settling for the six-cylinder variety. BMW->ke178 and Mercedes->ke187 are two such companies that have already taken to downgrading the powertrain for their performance vehicles and now, it appears that Audi->ke14 is following suit.

Word from Car and Driver seems to indicate that the German company will be using turbocharged V-6 engines on its RS-branded lines, including the RS4->ke742. No longer will the company's sports line hitting production V-8, instead the focus will now center on those turbo V-6s, smaller in displacement but no less powerful once you add those turbochargers into the mix.

That's looking like Audi's->ke14 plan for the RS4, which really is as much a return to its previous form than it is a downgrade of sorts. After all, as recent as 2001, the RS4 Avant packed a 2.7-liter, twin-turbo V-6 under its hood, so it's not like Quattro GmbH is venturing into unchartered territory when it comes to marrying the two sides together.

The important thing for the RS4 is to not cheapen its value relative to the new BMW M4->ke4183 and the redesigned M3->ke2366. It wouldn't look too good for Audi if it cut power from its prized sports wagon, so you can still expect the vehicle to generate more than 400 horsepower.

Anything less would spell trouble for Audi given that its predecessor already had 450 ponies and other manufacturers have seemingly integrated those turbocharged V-6s into producing stout levels of output.

Only time will tell what Audi has in store for the RS4, but if those twin-turbo V-6s carry their weight, nobody's going to be crying a river over the loss of those V-8s.

Note: Current Audi RS4 Avant pictured here.

Click past the jump to read more about the 2016 Audi RS4.

Competition

2014 BMW M3

BMW unveiled the new-generation M3 sedan back in December 2013, before the car was initially launched on the virtual world of Gran Turismo 6 racing game.

The M3 uses a 3.0-liter, twin-turbocharged, I-6 that delivers 425 horsepower between 5,500 and 7,300 rpm, and 406 pound-feet of torque between 1,850 and 5,500 rpm. The engine is mated to either a standard six-speed manual transmission or a seven-speed M Double Clutch transmission.

The M3 is capable of sprinting from 60 mph in just 3.9 seconds with the seven-speed transmission or 4.1 seconds with the manual version.

2014 Cadillac CTS Vsport

The all-new CTS Vsport is one of the RS4’s key competitors, that is if the latter ever makes its way into US soil. As far as the CTS Vsport goes, it sure makes good use of its new 3.6-liter, twin-turbocharged V-6 engine, doesn't it? That baby cranks out 420 horsepower and 430 pound-feet of torque.

We also love the new look of the CTS, something that should ring music to the ears of Cadillac execs who are determined to bring its performance sedan into becoming more of a player in the market.

History

First introduced in Avant form back in 1999, the Audi RS4 has evolved into becoming one of the more exciting sports sedans in the market, a trait you can attribute to the successful way by which Audi has nurtured the lineup all these years.

Fast forward to the current-generation RS4, and you can immediately tell the growth the model has had since its infancy a little more than a decade ago. The 2013 RS4 Avant made use of Audi's core RS design principles, highlighted by its fancy hexagonal single-frame grille with a matte aluminum-look finish and its honeycomb insert finished in a high-gloss anthracite.

And while it's becoming clear that Audi is changing into a V-6 for all future RS4 models, the 2013 still carries a 4.2-liter V-8 engine - borrowed from the RS5 - that delivers a total of 450 horsepower. This engine sprints the car from 0 to 60 mph in just 4.7 seconds - an impressive number for a station wagon model.