Deep in the primieval, sub-tropical forests
close to where I live we swish past spotted gums, bottle brush, a huge variety
of eucalyptus trees, and the very ancient cicad ferns and other remnants of the volcanic birth of this beautiful, mountainous landscape.
Swishing is the most appropriate term I can
use to describe my recent test drive of the 2016 Jaguar XF S sedan. The power,
pointing ability and agility of this latest Jaguar is just a sheer delight.
The XF S dives into tight corners, and a
combination of its clever vectoring software, light weight, and near 50-50
balance means you hit the apex on cue, and groove out the exit, pressuring the
supercharged 3.0L V6 to come on song and ‘swish’ you into the next tight
challenge.
When you emerge after descending the
mountain onto the flat, open highway the pleasure continues as you wind up the
pace and sit there with a smile on your face.
The XF S is a beautifully
composed machine which provides a scintillating driving experience courtesy of
some of the cleverest engineers around.
Mike Cross and his mates in the dynamics
department at Jaguar have superbly refined what is essentially a passive suspension,
plus electronic damping control. They’ve done a superb job.
The double wishbone front suspension, and rear
integral link design sounds almost too simple a way to describe how the results
stack up, on the road.
Being an old Jaguar hand, plus many
hundreds of kilometres road-testing Jaguars from the 1968 XJ, through to the
1986 XJ-40 as an auto journalist, I have always admired the quality of the ride
and handling of the cats from Coventry.
Jaguars have always been famous for
outstanding primary and secondary ride characteristics, thanks to the skill of
its engineers and outstanding basic design. However, the achievements the
engineers have delivered with this latest XF range are exemplary.
The new XF is 4954mm long, and height is 1465mm. The new car is 7mm shorter and 3mm lower. Passenger comfort is said to be helped by the new XF’s longer wheelbase, which now measures 2960mm, making it 51mm longer than the first generation.
(Here is a reprint of an interview with The Automotive Engineer magazine).
The new XF is 4954mm long, and height is 1465mm. The new car is 7mm shorter and 3mm lower. Passenger comfort is said to be helped by the new XF’s longer wheelbase, which now measures 2960mm, making it 51mm longer than the first generation.
(Here is a reprint of an interview with The Automotive Engineer magazine).
Jaguar’s Paul Atkins describes the approach
to the XE/XF):
“The XE/XF has a new modular
suspension architecture with double wishbone front suspension and an integral
end rear suspension. This is the first of its type in the D-segment and
something our competitors only utilise on cars in the segment above.
Rear suspension |
“The advantage of the integral
link over a generic multi-link suspension is it separates out the lateral
and longitudinal forces from the vertical. The link also allows us to have
softer suspension bushes: the bushes on the XE/XF are around 30% softer than our competitors.
“The XE is available with both
passive and active damping systems. Passive suspension is a classic arrangement
of coil over dampers on the front, and a coil spring and damper separated on
the rear.
“We’ve utilised new springs, which
have a lighter, thinner material for further weight saving. They’re a dual-rated spring, meaning the initial travel is softer for a comfortable luxury
ride, but as the spring compresses, the rate increases, delivers sports car
like body handling.
Front suspension |
"The new passive dampers enable frequency-dependent damping – the ability to vary damping force not only with the velocity that the damper piston moves at, but also as a function of its frequency.
"In the XF active system an extra valve in the piston provides an additional bypass. At road speeds typical of town driving, the valve is open, allowing some fluid to flow through it instead of the main valve in the piston. With increasing speed the valve closes, forcing all of the fluid to pass through the piston: damping force increases and the ride becomes firmer.
“One of the headlines for the
Jaguar XE/XF is the introduction of electronic power assisted steering – it's a
motor on the rack ZF system – a first for Jaguar.
“One of the early problems with
electronic power assisted steering was the friction in the internal gears, and
we’ve introduced an entirely new system, which is able to compensate for that
friction. It understands what the driver is demanding, and ensures that it
delivers the appropriate output.
“It’s also able to serve in
hot-cold temperature and ensure that the delivery is consistent whatever the
climate, and it also helps with economy. Because there’s no hydraulic pump on
the engine, it’s able to deliver CO2 cuts of 3% on the gasoline engines, and 2%
on the diesels.
“Assistance varies with speed,
allowing greater assistance at parking efforts, and it also adapts to the
profile selected by the driver, on the Jaguar drive control system.
Additionally, we were able to employ variable damping, so the appropriate
response is given to a brisk input on a spirited drive, or a relaxed motorway
cruise.
“When we developed the electronic
power steering, we found it was small things that made a big difference. We’ve
implemented soft lock stops, so as you reach the limits of travel on the
steering, rather than the traditional harsh stop of metal on metal, you will
feel a cushioned response, generated from the electronic control.
“We also have drift compensation,
which helps to counteract the car’s natural tendency to follow the camber of
the road. This ensures the car will track true and straight, even if the driver
doesn’t.
“A new feature for Jaguar is all
surface progress control. An all new traction control technology designed to
help the driver pull away on slippery surfaces and make the most of the grip
that’s available.
“We’ve developed new techniques
for tackling noise, vibration and harshness, and tailored these to the
architecture.
“Firstly, we produced the
stiffest, most lightweight body structure, and suspension components have been
optimised for reduced NVH. The new XF is 28% stiffer and 11% lighter than the previous model.
NOTE: Most of the structural components are joined by Australian-designed and developed aluminium self-piercing rivets, and high-strength adhesives.
"The suspension bushes transmit minimum levels of road noise, and as we took out sound intrusion, high frequency harshness and low frequency boom has been eliminated from the car, to deliver a refined basis for the new XE/XF.”
The XF S is powered by the (280kW)
AJ126 engine, a 90 degree V6 derived from Jaguar’s superb AJ-V8 engine, first
introduced in 1997.
Whilst 90 degrees is not the optimal
arrangement for a V6, Jaguar has achieved excellent smoothness and power
delivery thanks to Bosch high pressure fuel injection, lightweight alloy
construction and the location of the supercharger inside the ‘V’ of the engine.
Fuel economy on my drive was 8.8 L/100km.
Fuel economy on my drive was 8.8 L/100km.
Given my deep personal links to
Jaguar, you’ll have to forgive my glowing assessment of this car, but I invite you to
read what many others have said after testing the latest XF. It is a joy to
drive and as an indicator of Jaguar’s progress into the heart of the D-segment
sports sedan market, it is an outstanding and impressive car.
I would go so far as to say it’s
SUPERB!
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