Instrumented Test
From the July 2014 Issue of Car and Driver
Infiniti’s new Q50 is more advanced and mature than the G37 sedan it replaces, but that’s not to say it’s better. Our previous tests have shown it to be wayward and lacking in feel when fitted with the optional by-wire Direct Adaptive Steering (DAS) system. While the company tries to make good with a new performance-tire package and the first of what will surely be many software updates for the innovative helm, simply opting for the car’s conventional steering clears the electronic fog from the drive.
DAS’s electric motors, control modules, and steering-force sensor in the column can only synthesize forces acting on the Q50’s front tires’ contact patches (a mechanical link is in place as backup). The base steering arrangement is still electrically assisted, yet it feels more natural because of its direct mechanical connection to the front wheels.
The conventional rack is more predictable and better matched to the Q50’s dynamics. Whereas DAS filters out every poke and prod from the road surface, the base setup reacts with familiar nudges of feedback and a buildup of effort proportional to cornering forces. It’s still less talkative than we’d prefer—and still shy of the bar set by the old G37. But it beats DAS.
At the track, our rear-drive Q50S test car posted stronger results thanks to its newly available Bridgestone summer tires (245/40 in front, 265/35 out back) on new 19-inch wheels, now offered for rear-drive models in place of the standard 19s with symmetrically sized Dunlop 245/40s. The optional tires boosted grip on the skidpad to 0.95 g, up from 0.88 g for the last Q50S we tested. Stops from 70 mph improved slightly, down to 156 feet, while acceleration to 60 mph quickened by 0.2 second.
The steering wheel is connected to the front wheels. Optional wheels save about eight pounds each, add strange blue cast.
While Infiniti is asking a very dear $4300 for the flashy new rollers and sticky tires, the Q50’s conventional steering system comes at no cost on nonhybrid Qs (DAS is fitted to all Q50 hybrids). Still, Infiniti punishes your neo-Luddism by locking you out of some option packages. Forget the $3100 Deluxe Touring package (power tilt-and-telescoping steering column, split-folding rear seats, the Around View Monitor, and auto-dimming mirrors) because it’s bundled with DAS. And because Deluxe Touring is required to get the $3200 Technology package, Infiniti’s suite of collision-avoidance helpers also is beyond reach—though we consider that a reward for people who can avoid collisions all by themselves.
A base Q50 starts at $37,955, and the S model on this page stickered at $50,955 with the new wheels and tires, a $1400 navigation system, and a few other extras.
We admire Infiniti’s commitment to the development of by-wire steering, but the technology is still a work in progress. Advances in onboard computing power may allow it to evolve over time, as have other driving aids such as ABS and stability control. But for now, the Q50 is best enjoyed with your brain, rather than the car’s, behind the wheel.
