2015 Acura RLX Sport Hybrid vs Infiniti Q70L

Space Age vs Spacious


Acura hailed the RLX as its most sophisticated product to date when it arrived for the 2014 model year. Sadly, Nobody was listening.

In its first full year on the market, only 3,413 copies of the RLX sold and 2015 is off to a rough start. It’s too early to tell how the rest of the year will go, but RLX sales are down almost 54 percent in the first quarter of 2015 compared to last year.

Meanwhile the aging Infiniti Q70 (formerly the M) is outperforming the RLX despite its lack of an up-to-the-minute powertrain.

Powertrain Re-Cap

To recap, the RLX is available with either front- or all-wheel drive. The less expensive front-wheel drive models get all-wheel steering to improve cornering agility and braking, but the all-wheel drive model is Acura’s real piece de resistance.

It uses a 3.5-liter direct injection V6 mated to an electric motor and a seven-speed dual-clutch transmission that work in concert to power the front wheels. A pair of electric motors power the rear wheels independently. They can also individually brake to offer something akin to – but not the same as – rear-wheel steering for enhanced handling.


Infiniti sells the Q70 with either rear- or all-wheel drive layouts with provision for a V6 or V8 with a regular or extended wheelbase as well as a hybrid model. Six-cylinder models use multi-port injection while the V8 takes advantage of direct injection. Regardless of which engine type you choose, the Q70 comes with a seven-speed automatic.

2015-Acura-RLX-vs-Infiniti-Q70L-41Acura’s hybrid technology boosts the V6 powertrain to a total of 377 HP, which isn’t as robust as the V8 Q70 with 416, but it’s still quick from a dead stop. The 5.6-liter V8 will tug the Q70 off the line with purpose, but that power comes with a significant pump tax.

Gulps Per Gallon

In an identical loop, the Q70 – equipped with all-wheel drive, the V8 and the extended wheelbase – averaged an eye watering 13 MPG. The RLX Sport Hybrid got 22.4 MPG. It’s true that the Infiniti is more powerful, but the extra muscle isn’t worth suffering through such poor mileage to enjoy.

Ride Comfort

But the Infiniti Q70 has other advantages that might make it worthwhile even if it is a gas-guzzler. Compared to the RLX, it has a smooth ride better damped to disguise broken pavement. It also offers you a greater breadth of options than Acura can because there are a greater number of variants. For example, the all-wheel drive V8 extended wheelbase model offers an extra three inches of legroom and almost an extra inch of headroom in the second row at a $1,700 premium over the regular wheelbase model. Even with all the extra space, it is still nine pounds lighter than the RLX Sport Hybrid.

A bloated curb weight isn’t the only area Acura’s car takes a hit. It sacrifices trunk space and a folding rear seat to house most of its hybrid components. In the end, it only has 12 cubic feet of trunk space.


AWD: Tradition Beats Technology

The Infiniti’s traditional all-wheel drive system also transfers power as smoothly as you would expect from such a system. While cornering, the RLX Sport Hybrid’s rear electric motors create a sensation of resistance that isn’t inexcusably jarring, but it’s noticeable and unpleasant. It seems as if Acura’s new hybrid all-wheel drive system needs work before it can stand shoulder-to-shoulder with traditional mechanical systems.


But that’s really the only part of the powertrain that stands out in a negative way. Acceleration is smooth, quiet and relatively efficient for a sedan that weighs 4,354 lbs.

Steering is lighter in the Acura than the Infiniti, but not to a fault. The RLX cabin is neatly assembled with high quality materials that feel appropriately in context save the touch screen. Its menus are confusing at times and can be more difficult to navigate than what you will find in the Infiniti.

And that isn’t the only place where the Q70L’s interior has an edge because the front seats and armrests are also more ergonomic in the Infiniti.

2015 Acura RLX Sport Hybrid vs Infiniti Q70L

Compare Specs

2015 Infiniti Q70L
2015 Acura RLX Sport Hybrid
Vehicle 2015 Infiniti Q70L Advantage 2015 Acura RLX Sport Hybrid
Engine 5.6-liter V8 3.5-liter V6, 3 electric motors
Transmission seven-speed automatic RLX Sport Hybrid seven-speed dual-clutch automatic
Horsepower 416 Q70L 377
Torque 414 lb-ft Q70L 341 lb-ft
Wheelbase 120.1 inches 112.2 inches
Length 202 inches 196.1 inches
Curb weight 4,345 lbs Q70L 4,354 lbs
Front seat headroom 39.1 inches Q70L 37.6 inches
Front seat legroom 44.4 inches Q70L 42.3 inches
Rear seat headroom 37.7 inches Q70L 36.9 inches
Rear seat legroom 41.8 inches 38.8 inches
Cargo capacity 14.9 cubic feet Q70L 12 cubic feet
Starting price (US) $67,995 RLX Sport Hybrid $60,845
As-tested price (US) $67,995 RLX Sport Hybrid $66,845
Observed fuel economy (US) 13 MPG RLX Sport Hybrid 22.4 MPG
Starting price (CDN) $70,395 Q70L $72,119
As-tested price (CDN) $70,395 Q70L $72,119
Observed fuel economy (CDN) 18 l/100 KM RLX Sport Hybrid 10.5 l/100 KM

Value Proposition

Infiniti would have the fight sewn up without breaking a sweat if that were the whole story, but as usual there’s more.

We borrowed an RLX Sport Hybrid loaded with the “Advance Package” that includes adaptive cruise control, a lane keeping assistance system, heated front and rear seats, cooled front seats and a 14-speaker premium audio system to name a few. That package brings the price to $66,845 including delivery. The Infiniti Q70L comes with most of those upgrades except for the safety systems like adaptive cruise control and lane-keeping assistance provided you buy the V8. So equipped, it runs $67,955. The same safety technology is still available, but it calls for the $7,200 “Deluxe Technology Package” which slingshots the price to $75,155.

2015-Acura-RLX-vs-Infiniti-Q70L-4 2015-Acura-RLX-vs-Infiniti-Q70L-13 2015-Acura-RLX-vs-Infiniti-Q70L-72015-Acura-RLX-vs-Infiniti-Q70L-16

Suddenly, the RLX doesn’t seem so bad after all. Sure the ride is rougher, but in exchange you get fuel efficiency akin to a much smaller and less powerful vehicle. The Infiniti’s interior design is more grandiose, but you’ll wind up spending roughly $8,000 more on it to enjoy the same convenience features as you would in the RLX.


The Verdict:

Even if the RLX doesn’t have the same premium feeling as the Q70, we would recommend it based on fuel economy and value for the money. After all, that’s what buying a luxury sedan from Honda or Nissan is all about. Isn’t it?

2015 Infiniti Q70L AWD

2015 Acura RLX Sport Hybrid