The Acura RLX was introduced in 2013 for the 2014 model year and served as a follow-up to the second-generation RL, which at the end of its lifespan was in desperate need of replacement. Like the RL, the RLX has its sights set on the midsize luxury segment,->ke505 which includes the BMW 5 Series->ke317 and Mercedes-Benz E-Class.->ke373 It’s powered by a 3.5-liter V-6 producing 310 horsepower, but unlike most of its German rivals, it puts it power down through the front wheels -- a potential turn-off for some buyers. Fortunately, Acura->ke10 has addressed this shortcoming with the Sport Hybrid SH-AWD.

The RLX Sport Hybrid SH-AWD is Acura’s new flagship, and has the potential to be a game-changer when Acura needs it the most. Acura’s range has been a bit stagnant these past few years. Much of the sporting juju Acura earned with cars like the original NSX,->ke307 Integra,->ke1527 and RSX has been largely forgotten thanks to years of building extraordinarily average sedans->ke142 and SUVs->ke145 that haven’t quite been able to take the fight to rivals from Germany and Japan.

This newfound swagger comes with its innovative new Super Handling all-wheel-drive hybrid->ke147 drivetrain. Unlike other hybrids in its sector the RLX Sport Hybrid’s electric motors and batteries don’t just improve fuel economy, they also add healthy dose of power and actually improve performance rather than hinder it. More on this later, but for now, we can view the RLX Sport Hybrid as a luxury sedan that previews the next NSX’s drivetrain.

Click past the jump to read more about the Acura RLX Sport Hybrid SH-AWD.

Exterior

Styling is instantly recognizable as an Acura, but the company has put itself in a position where it’s now difficult for even a trained eye to tell an ILX, from a TLX, from an RLX. Acura’s sedans aren’t by any means offensive to look at, but you do get the sense the company is playing it a bit safe. The RLX doesn’t really move the game on all that much from the RL, which had already overstayed its welcome by about three years. Acura’s cool “Jewel Eye” LED headlamps are easily the RLX’s most unique and eye-catching exterior feature.

Size-wise, the RLX falls comfortably into the midsize luxury class also occupied by the BMW 5 Series, Mercedes-Benz E-Class, and Lexus GS. At 196.1 inches in length it’s about 3 inches longer than the BMW 5 Series, but its wheelbase is nearly 5 inches shorter at 112.2. Its body utilizes both steel and aluminum body panels, which Acura says keeps weight to a minimum and aids handling, braking, acceleration and fuel economy.

Exterior Dimensions

Interior

The interior is relatively familiar Acura fare. Surfaces appear high-quality, but there’s not much in the way of interior customization. Weirdly, the Technology Package interior is available in both ebony and graystone leather, while the Advance Package is only available in ebony. Both are trimmed with dark mahogany-like accents, and controls appear ergonomic and well positioned.

The infotainment and sat-nav screens are stacked on top of one another and are both suitably large. Bluetooth, hands free phone, blind spot detection, phonebook, acoustic glass, and music app compatibility are also standard.

Drivetrain

Underneath the RLX Sport Hybrid's staid styling lies its real party trick. The market is flooded with luxury hybrids, but none utilize their electric motors the way the RLX Sport Hybrid does. The drivetrain consists of a 310 horsepower, 3.5-liter, i-VTEC V6 and three electric motors: one up front mounted inside in the seven-speed dual-clutch gearbox and two at each of the rear wheels. There are no rear drive shafts or rear differential; all power to the rear wheels is generated exclusively by the two 36-horsepower electric motors.

Here’s where things get interesting. Both rear motors distribute both positive torque for propulsion and negative torque under regenerative braking to harvest and store energy as electricity, and they’re able to do this completely independent of one another. This torque vectoring allows from some intriguing possibilities. In certain scenarios, the RLX Sport Hybrid is capable of applying 100 percent of its torque to the outside wheel while cornering, and negative torque to the inside rear wheel. It’s a revelation in terms of handling and does a great job of mitigating understeer. It also cleverly disguises the RLX Sport Hybrid’s substantial weight penalty over the non-hybrid RLX, though the hybrid does boast improved weight distribution.

Between the internal combustion engine and the three electric motors, the RLX Sport Hybrid produces a formidable 377 horsepower and 341 pound-feet of torque. The 0-to-60 sprint takes an impressive five seconds flat, all while returning 32 mpg on the highway and 28 in the city.

Drivetrain/Specifications

Prices

The RLX Sport Hybrid SH-AWD starts at $59,950 and comes in two trim levels. The base Technology Package comes standard with an electronic gear selector, a heads-up display, heated seats and a reactive-force accelerator pedal (which applies reactive force to help the driver apply power as efficiently as possible). Adding another $6,000 will get you the Advance Package, which adds collision detection, lane assist, adaptive cruise control, Krell premium audio system, heated rear seats and rear footwell lighting.

Competition

BMW ActiveHybrid 5

The Acura out-muscles the similarly priced BMW ActiveHybrid 5 by some margin, but it can’t match the BMW in terms of customization. The ActiveHybrid 5 offers more interior color options, as well as some nifty optional M Sport bodywork.

At 5.9 seconds, the ActiveHybrid 5 is nearly a second off the Acura’s 0-to-60 time, but what it lacks in straight-line performance, it makes up in fuel economy, getting 40 mpg on the highway to the Acura’s 32 mpg. It’s powered by BMW’s 3.0-liter straight six, and is augmented by a pair of turbochargers and a single electric motor. In total, it produces 340 horsepower and is capable of driving up to 2.5 miles on electric power alone. The BMW also has an eight-speed transmission to the Acura’s seven, but at that point, who’s counting?

With an asking price of $61,845, it’s somewhere between the RLX Sport Hybrid’s two price points, but the BMW has the superior interior, which is hard to pass up.

Mercedes-Benz E400 Hybrid

At $56,700 the Mercedes-Benz E400 Hybrid is appreciably less expensive than both the Acura and the BMW, and, like the BMW, it’s infinitely more customizable both inside and out.

It’s powered by a normally aspirated, 3.5-liter V-6 and a single electric motor producing a combined 329 horsepower. At 30 mpg on the highway, it’s lagging a bit behind the Acura at 32 mpg, and way behind the BMW at 40 mpg. Unlike many hybrids, it actually gets worse mileage under city driving conditions -- 24 mpg to the BMW’s 44 and the Acura’s 28 in the city.

Overall, I am a big fan of the styling of the current E-Class. The new one-piece LED headlamps and horizontal taillights give it a thoroughly modern appearance, but it’s also instantly recognizable as a Mercedes.

Lexus GS 450h

Lexus offers two different versions of its GS hybrid starting at $60,430, the base GS 450h and the GS 450 Hybrid F Sport, but, other than some visual and suspension upgrades for the F Sport, there’s no discernible difference in performance or efficiency between the two.

We really liked the GS 450h when we drove it last month, but, on paper at least, the RLX Sport Hybrid has it beat. With 34 mpg on the highway, the GS has a slight edge in terms of fuel economy, but is over half-a-second slower to 60 mph. But we like that it’s a relatively powerful (338 horsepower) rear-wheel-drive luxury sedan that’s fun to drive. Go for the optional sport suspension too. It’s rather good.

We weren’t fans of the cheap-looking interior wood trim, but the GS hybrid does come with plenty of well-appointed standard features. We also felt the drivetrain would have been better served with a traditional automatic or dual clutch transmission rather than Lexus’ CVT.

Conclusion

It will be interesting to see if the Sport Hybrid SH-AWD drivetrain gets applied to other platforms in Acura’s, or even Honda’s, range. We already know a similar system will power the forthcoming NSX, which will feature the same torque-vectoring tricks. It would also seem to make sense on Acura’s soft-roaders, the RDX and MDX.

The RLX Sport Hybrid applies this new technology well, but we’d like to see some sporty visual queues to help differentiate it from the base RLX. As it is, trying to pick out differences between the two is like playing a really, really hard version of one of those touch-screen spot the difference game. Given the changes under the skin and sporty pretenses, we’d like to see something a bit meaner looking.

Looks and options aside, parent company Honda changed engine technology forever with innovations like VTEC and CVCC. Let's see if it can make history again with its trick new all-wheel-drive hybrid drivetrain. The RLX Sport Hybrid is just the first step.