Compare the2018 Infiniti Q50VS 2017 Acura RLX

Over 200 people are killed each year when backed over by motor vehicles. The Q50 (except Pure) offers optional Back-up Collision Intervention which use rear sensors to monitor and automatically apply the brakes to prevent a rear collision. The RLX doesn’t offer backup collision prevention brakes.

Both the Q50 and the RLX have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, height-adjustable front shoulder belts, four-wheel antilock brakes, traction control, electronic stability systems to prevent skidding, daytime running lights, rearview cameras, available all-wheel drive, crash mitigating brakes, lane departure warning systems, blind spot warning systems, around view monitors and rear cross-path warning.

The National Highway Traffic Safety Administration does side impact tests on new vehicles. In this test, which crashes the vehicle into a flat barrier at 38.5 MPH and into a post at 20 MPH, results indicate that the Infiniti Q50 is safer than the Acura RLX:

New test not comparable to pre-2011 test results. More stars = Better. Lower test results = Better.

The Q50 comes with a full 4-year/60,000 mile basic warranty, which covers the entire car and includes 24-hour roadside assistance. The RLX’s 4-year/50,000 mile basic warranty expires 10,000 miles sooner.

The Q50’s corrosion warranty is 2 years longer than the RLX’s (7 vs. 5 years).

From surveys of all its subscribers, Consumer Reports’ April 2017 Auto Issue reports that Infiniti vehicles are more reliable than Acura vehicles. Consumer Reports ranks Infiniti 4 places higher in reliability than Acura.

The Q50 Red Sport 400’s 3.0 turbo V6 produces 23 more horsepower (400 vs. 377) and 9 lbs.-ft. more torque (350 vs. 341) than the RLX Sport Hybrid’s optional 3.5 SOHC V6 hybrid.

As tested in Motor Trend the Q50 Hybrid 3.5 DOHC V6 hybrid is faster than the Acura RLX V6:

As tested in Car and Driver the Q50 Red Sport 400 3.0 turbo V6 is faster than the Acura RLX (base engine):

On the EPA test cycle the Q50 2.0t RWD gets better city fuel mileage than the RLX FWD V6 (23 city/30 hwy vs. 20 city/30 hwy).

The Q50 Hybrid’s standard fuel tank has 2.7 gallons more fuel capacity than the RLX Sport Hybrid’s standard fuel tank (17.8 vs. 15.1 gallons), for longer range between fill-ups. The Q50’s standard fuel tank has 1.5 gallons more fuel capacity than the RLX’s standard fuel tank (20 vs. 18.5 gallons).

For better stopping power the Q50’s front brake rotors are larger than those on the RLX:

The Q50’s standard front and rear disc brakes are vented to help dissipate heat for shorter stops with less fading. The rear discs on the RLX are solid, not vented.

The Q50 stops much shorter than the RLX:

The Q50 Red Sport 400’s 265/35R19 rear tires provide better handling because they have a lower 35 series profile (height to width ratio) that provides a stiffer sidewall than the RLX’s 40 series tires.

Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires available on the Q50 can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The RLX doesn’t offer run-flat tires.

The Q50 Red Sport 400 RWD offers an optional space-saver spare tire so you can replace a flat tire and drive to have the flat repaired or replaced. A spare tire isn’t available on the RLX; it requires you to depend on roadside assistance and your vehicle will have to be towed.

The Q50 offers an optional driver-adjustable suspension system. It allows the driver to choose between an extra-supple ride, reducing fatigue on long trips, or a sport setting, which allows maximum control for tricky roads. The RLX’s suspension doesn’t offer adjustable shock absorbers.

The Q50’s optional drift compensation steering can automatically compensate for road conditions which would cause the vehicle to drift from side to side, helping the driver to keep the vehicle straight more easily. The RLX doesn’t offer drift compensation steering.

The Q50 handles at .95 G’s, while the RLX pulls only .84 G’s of cornering force in a Car and Driver skidpad test.

The Q50 executes Motor Trend’s “Figure Eight” maneuver 1.8 seconds quicker than the RLX (25.5 seconds @ .76 average G’s vs. 27.3 seconds @ .64 average G’s).

For better maneuverability, the Q50’s turning circle is 3.8 feet tighter than the RLX’s (36.7 feet vs. 40.5 feet). The Q50 AWD’s turning circle is 3.1 feet tighter than the RLX’s (37.4 feet vs. 40.5 feet).

The Infiniti Q50 may be more efficient, handle and accelerate better because it weighs about 150 to 300 pounds less than the Acura RLX.

The Q50 is 6.5 inches shorter than the RLX, making the Q50 easier to handle, maneuver and park in tight spaces.

The Q50 has 2.6 inches more front headroom, 2.2 inches more front legroom and .6 inches more rear headroom than the RLX.

The Q50’s optional rear seats fold to accommodate long and bulky cargo. The RLX doesn’t offer folding rear seats, only a ski pass-through.

The engine in the Q50 is mounted longitudinally (North-South), instead of sideways, as in the RLX. This makes it easier to service and maintain, because there are no rear spark plugs and the accessory belts are in front.

The Insurance Institute for Highway Safety (IIHS) conducts detailed tests on headlights for their range both straight ahead and in curves and to be certain they don’t exceed acceptable amounts of glare to oncoming drivers. The Q50’s available headlights were rated “Acceptable” by the IIHS, while the RLX’s headlights are rated “Marginal.”

While driving with high beams on, sensitive light sensors available for the Q50 3.0t/Red Sport 400 detect other vehicles which could be blinded and automatically switch to low beams. The RLX doesn’t offer automatic dimming high beams.

To help drivers see further while navigating curves, the Q50 Premium/Sport offers optional adaptive headlights to illuminate around corners automatically by reading vehicle speed and steering wheel angle. The RLX doesn’t offer cornering lights.

The Q50 will cost the buyer less in the long run because of its superior resale value. The IntelliChoice estimates that the Q50 will retain 37.69% to 40.56% of its original price after five years, while the RLX only retains 33.29% to 35.23%.

IntelliChoice estimates that five-year ownership costs (depreciation, financing, insurance, fuel, fees, repairs and maintenance) for the Infiniti Q50 will be $7916 to $22984 less than for the Acura RLX.

The Infiniti Q50 outsold the Acura RLX by over 29 to one during the 2016 model year.