Rarely does an automaker choose the world's most dangerous roads to introduce a new vehicle to the media. So Jaguar's recent launch of the all-new 2017 F-Pace sports crossover in the mountains of Montenegro—where poor surfaces, unguarded sheer drop-offs and narrow, unexpected hairpin bends are routine—was a brave decision indeed.
Such take-it-to-the-limit testing is typically reserved for vehicle development teams, but the route and sensational topography clearly gave Automotive Engineering and other select media good insight into F-Pace's dynamic capabilities and its four-year development.
"We call it our practical sports car," explained Andy Whyman, the Vehicle Program Director. Clearly F-Pace marks a whole new direction for a company whose basis is sports cars and luxury sports sedans.
It might seem more logical for this aluminum-intensive, road-biased SUV to wear a Range Rover badge—the majority of production, after all, will be all-wheel drive (AWD). But rear-drive-only versions will be offered in some markets and dynamically, F-Pace feels like a taller, more commodious sibling of Jaguar's XF and XE sedans. There is a "Jaguaresque" balance of ride, handling and steering in this vehicle that is immediately apparent.
Adaptive chassis control
Although not in the Land Rover league for off-road adventuring, the F-Pace has been designed to tackle some rough stuff. It has aluminum double wishbone front suspension, with lower arms designed to protect against accidental grounding. And anti-rollbar bushings are bonded to give added protection against dirt or sand ingress.
Rear suspension is an integral-link system with high lateral stiffness. Said Whyman: “It allows us to separate vertical and lateral compliance to give much better performance than conventional systems." Passive monotube dampers are tuned for on-road performance, and for smooth progressive response on rutted or broken surfaces.
The F-Pace is available with Jaguar’s adaptive dynamic chassis system. It measures driver inputs and vehicle responses up to 500 times per second taking data from 18 sources. It is driver configurable. Optional 22-in wheels are available with road tires specially developed to give what Whyman claims is the largest rolling diameter and radius of any current sports crossover.
“They have deep sidewalls for ride quality. Also, we have double the curb protection of our key competitors,” he added.
Traction technology includes adaptive surface response (AdSR) to optimize traction on ice, gravel, sand or snow. All Surface Progress Control (ASPC), utilizing the car’s cruise control to set low speeds on both very steep up and down slopes. Low Friction Launch (LFL) provides smooth pull away in challenging conditions.
1400 N·m front diff capability
The heart of the vehicle's rear-wheel-biased AWD is a compact, chain-driven, wet-clutch transfer case that is "10% more efficient and 16% lighter than previous generations,” explained Whyman. The front differential is capable of handling 1400 N·m (1032 lb·ft). Torque-on-demand is controlled by driveline dynamics software developed in-house from the F-Type sports car. The algorithms provide RWD-like agility and help counter the understeer that is inherent in AWD set-ups. The system transitions from 100% rear-bias to a 50:50 torque split in a claimed 165 ms. If there is already a proportion of torque being sent to the front axle, additional torque transfer takes place in 100 ms.
Many of the F-Pace’s safety features employ the forward-facing stereo camera. Autonomous Emergency braking is standard and incorporates pedestrian protection, spotting people in the vehicle’s path, alerting the driver or if necessary, stopping the vehicle.
The new Jag offers a wide choice of powertrains, including a twin-vortex supercharged 3.0-L gasoline V6 also used in the F-Type. It provides 0-100 km/h acceleration in 5.5 s (280 kW version). There are also two diesels: a 3.0-L twin turbo V6 with 700 N·m (516 lb·ft) that is claimed to be capable of 0-100 km/h in 6.2 s, and a 2.0-L "Ingenium" 4-cylinder unit producing 132 kW (177 hp), with 430 N·m (317 lb·ft) available from 1750 to 2500 rpm.
A 6-speed manual gearbox is available with the RWD driveline, with 129 g CO2/km emissions claimed for the 2.0-L diesel. V6 models use the same ZF 8HP70 8-speed as the sedan and F-Type.
Recycled aluminum target by 2020
The F-Pace is being built at Jaguar’s new purpose created flexible Solihull manufacturing center (70 new robots in the bodyshop) alongside the Jaguar XE. Use of modular aluminum architecture is a major element of F-Pace design, allowing the company to increase "the breadth of products we can introduce and reduces the time taken to create them," explained Kevin Stride, Vehicle Line Director.
He added that the vehicle personalization that Jaguar customers demand is another design attribute that is not possible to engineer using a high degree of bill-of-material commonization with the sedans. Stride claimed that 81% of F-Pace components are not shared with XE or XF. For example, its HPDC (high pressure diecast) aluminum front suspension turrets and the entire front subframe are unique to the SUV and enable greater ground clearance and suspension travel.
Jaguar has its own aluminum grade, RC5754 and the company is "constantly increasing the percentage of aluminum used in our cars through smarter engineering and manufacturing," Stride said. Approximately 80% of the F-Pace’s body structure is aluminum; the core body-in-white weighs less than 300 kg (661 lb). One third of this is recycled material, by weight; Jaguar's goal is to get to 2020 using 75% recycled aluminum, he noted. The body is joined using more than 2600 self-piercing rivets, 72.8 m (238.8 ft) of structural adhesive and over 560 spot welds.
The car's hood is aluminum; doors are steel, the liftgate is composite, and front cradle is magnesium. All contribute to a near 50:50 front/rear weight distribution, Whyman said.
Over 100,000 machine-hours of CFD simulation resulted in a flat underfloor leading from the front splitter and a rear spoiler which contributes to a 50% lift balance between front and rear to achieve a best Cd of 0.34—which is a useful thing to have after you leave the mountain hairpins.
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