It’s not the way the 5.2-liter, twin-turbo V-12 storms to its 7,000-rpm redline, or the barrel-chested boom from the exhaust on the way there. It’s not the remarkable stability under heavy braking, either, or the wonderful tactility of the steering through the turns. Nope, the first thing that impresses about the 2017 Aston Martin DB11 is the quality of its ride.
We’re at Bridgestone’s European Proving Ground, south of Rome, not far from the beaches at Anzio where in World War II Allied forces landed to begin a grueling campaign to liberate the Italian capital from Nazi occupation. Aston Martin vehicle attribute engineering chief Matt Becker says the prototype we’re driving today is about 80 to 85 percent of where he wants it to be, but even now the DB11 feels special—quick, composed, and amazingly comfortable. It feels like a car you’d happily drive 1,000 miles in a day, arriving at your destination refreshed and ready for a glass of chilled Dom Perignon. It feels like a genuine gran turismo.
“Because this is a GT car, ride is so important,” says Becker, who joined Aston Martin after a 26-year career at Lotus that included working on suspension and chassis tune for cars such as the Elise and the Evora. Development of the DB11 was already well underway when he arrived. “My initial feeling was the steering was a little bit aggressive off-center,” he says, “but that allowed us to relax the primary motions in the car because we weren’t looking for support from anti-roll bars or spring stiffness or damping stiffness to make it responsive.”
In simple terms: Becker knew the DB11 didn’t need to ride like a Conestoga wagon to go around corners.
Thanks to the new Daimler-sourced electrical architecture, the DB11 boasts three selectable damping levels: GT, Sport, and Sport+. In the softest setting—GT—the ride is remarkably compliant, but, critically, the body motions are beautifully controlled. You can push the DB11 hard on the track in GT mode, and it doesn’t devolve to a wobbling mess. It stays straight under heavy braking, turns in nicely, and maintains its composure through the turn.
Switching to Sport and then Sport+ modes tames the body motions a little more and improves steering response, but the ride remains impressively supple for a car running 255/40ZR20 and 295/35ZR20 high-performance Bridgestone S007 tires front and rear. “My brief was I didn’t want to hit Sport or Sport+ and make the car uncomfortable,” Becker says. “I’d rather have a character change but keep the heave motions still fairly compliant and just add a bit more off-center steering response to add a bit more agility.”
Becker says at this point the DB11’s chassis development program is all about adding refinement. That includes final tuning of the stability-control system, which has three settings—On, Track mode, and Off—and is about 70 percent to where Becker wants it to be. Another part of the DB11’s dynamic arsenal still to be fine-tuned is brake-induced torque vectoring. “It’s really only working in a very small way at the moment because we wanted to get the basis of the car right first and then add the icing on the cake,” Becker says.
In the four weeks following our drive, Aston engineers will have been working with German supplier Continental, whose stability-control system the DB11 uses, to make sure the torque-vectoring setup complements the chassis. “We don’t want to use torque vectoring as a mask, but as a value-add,” insists Becker. “We’re not looking to use it much in GT mode unless somebody really needs it to get safely through a corner. We want to use it more as a pre-control system to make the car feel even more agile in Sport and Sport+ modes.”
Becker’s other challenge before he signs off the DB11’s chassis is final calibration of the EPAS steering system. And for the luddites who still moan that electric power steering lacks the feel and sensitivity of a hydraulically assisted setup, Becker has a simple retort: “EPAS is better.”
Why? “EPAS makes it easier to tune a better steering system because with hydraulics you are restricted,” he says. “You have a certain valve edge and torsion bar stiffness within the hydraulic system, and you have a flow curve, which drops the rate of assistance at a given speed. And that’s all you can do. To tune steering self-centering or effort gradient, you’re relying on caster or damping or other fundamentals in the suspension, which may cause other handling issues. With EPAS you can do it all independently.”
Out on the Bridgestone handling circuit the DB11’s steering is clear and concise; you can feel the front tires working up to the very edge of their friction envelope, and then you can feel—and hear—the slip angles building. It’s a relatively big coupe, the DB11—186.6 inches long and 76.4 inches wide, and rolling on a 110.4-inch wheelbase—but it’s a car you can drive with your fingertips. Part of the secret sauce here, says Becker, is the extremely rigid mounting of the steering rack to the front subframe and the extremely stiff steering column. “You don’t get any compliance through the steering column system, so all the information you want is fed to you when you drive.”
The DB11’s new electrical architecture also allows the selection of GT, Sport, and Sport+ modes for the engine and transmission. Switch the powertrain modes and chassis modes to Sport+, the stability control off, and the DB11 becomes entertainingly playful on the track. And it’s when you become aware that the brand-new 5.2-liter V-12 under the hood is packing a pair of twin-scroll turbochargers.
It’s a torque monster, this engine; all 516 lb-ft is present and correct from just 1,500 rpm and stays on duty until 5,000 rpm. Get aggressive with your right foot out of a tight turn, and you’ll light up those big rear tires, leaving two black streaks on the tarmac as the DB11 lunges away from the apex. The only other turbo telltale is the timbre of the exhaust note; the crackling snarl of the naturally aspirated, 5.9-liter engine has been replaced with a deep-throated roar. The engine revs briskly to 7,000 rpm, and the 600-hp power peak arrives at 6,500 rpm, just 250 revs lower down the range than in the old 5.9-liter, 565-hp Vanquish.
The rear-mounted eight-speed ZF automatic, connected to the engine, as in all current Aston Martins, via a torque tube, delivers crisp yet smooth shifts. There was a little lag using the paddles in Sport and Sport+ mode—final calibrations have still to be completed—but the new automatic is a major improvement over the six-speed used in the DB9.
Switching the stability control to Track mode still allows a little sideways fun in the DB11 but keeps a watchful eye on slip angles and traction. Switching the stability control back on and selecting Sport mode for both powertrain and chassis delivers a nice all-round compromise for fast, comfortable road driving.
All these modes are accessed via switches on the DB11’s steering wheel. The chassis settings are controlled by a switch on the left, powertrain settings by a switch on the right. Small graphics immediately to the left and right of the central tach/speedo display on the new 12-inch TFT-screen digital dash let you know at a glance what settings you’ve selected. Different modes also change the graphic presentation on the instrument panel.
Our prototype’s interior was finished in a particularly hideous pale blue leather—left over from a batch that failed durability tests, apparently—but even in its rough and ready state, with wires running to boxes bolted on the center console and racer tape slapped here and there, it’s clear the DB11’s cabin will deliver far superior levels of functionality and occupant comfort than any current Aston Martin. The new digital dash is legible and delivers all the additional information you’d expect in a modern car. The center stack switchgear is logically deployed, though Aston’s now-trademark push-button PRND layout is retained, and the fixed sat-nav screen now looks like factory fitment instead of something from Pep Boys.
We’ll get to spend time with fully baked 2017 Aston Martin DB11s in July when the car will be launched to the world media. But based on our wheel time in the car so far, we’re not expecting to be disappointed. This new DB11, which goes on sale in the U.S. in November with prices starting from $211,995, will be a benchmark Aston Martin.
2017 Aston Martin DB11 | |
BASE PRICE | $211,995 |
VEHICLE LAYOUT | Front-engine, RWD, 2+2-pass, 2-door coupe |
ENGINE | 5.2L/600-hp/516-lb/ft twin-turbo DOHC 48-valve V-12 |
TRANSMISSION | 8-speed auto |
CURB WEIGHT | 3,900 lb (mfr est) |
WHEELBASE | 110.4 in |
LENGTH X WIDTH X HEIGHT | 186.6 x 76.4 x 50.4 in |
0-62 MPH | 3.9 sec (mfr est) |
EPA CITY/HWY/COMB FUEL ECON | Not yet rated |
ON SALE IN U.S. | November 2016 |
View photos of the 2017 Aston Martin DB11 in non-prototype form right here:
The post 2017 Aston Martin DB11 Prototype Review: The Ride Stuff appeared first on Motor Trend.
from Motor Trend http://ift.tt/1Z14vHj
Aucun commentaire:
Enregistrer un commentaire