The XK has standard whiplash protection, which use a specially designed headrest to protect the driver and front passenger from whiplash. During a rear-end collision, the whiplash protection system moves the headrests forward to prevent neck and spine injuries. The 911 doesn’t offer a whiplash protection system.
Both the XK and the 911 have standard driver and passenger frontal airbags, front side-impact airbags, head airbags, front seatbelt pretensioners, four wheel antilock brakes, traction control and electronic stability systems to prevent skidding.
Jaguar pays for scheduled maintenance on the XK for 1 year and 12000 miles. Jaguar will pay for oil changes, tire rotation, lubrication and any other scheduled maintenance. Porsche doesn’t pay scheduled maintenance for the 911.
The XK has more powerful engines than the 911:
Torque |
|
XK8 4.2 DOHC V8 |
310 lbs.-ft. |
XKR 4.2 supercharged V8 |
413 lbs.-ft. |
911 3.6 DOHC 6 cyl. |
273 lbs.-ft. |
911 S 3.8 DOHC 6 cyl. |
295 lbs.-ft. |
911 GT3 3.6 GT3 6 cyl. |
300 lbs.-ft. |
As tested in Car and Driver the XKR is faster than the Porsche 911 6 cyl. (automatics tested):
XK |
911 |
|
Zero to 60 MPH |
4.5 sec |
5.2 sec |
Zero to 100 MPH |
10.9 sec |
12.5 sec |
5 to 60 MPH Rolling Start |
4.9 sec |
5.6 sec |
Passing 30 to 50 MPH |
2.4 sec |
3.1 sec |
Passing 50 to 70 MPH |
3.2 sec |
3.5 sec |
Quarter Mile |
13 sec |
13.8 sec |
Speed in 1/4 Mile |
109 MPH |
105 MPH |
The XK has 1.8 gallons more fuel capacity than the 911’s standard fuel tank (18.7 vs. 16.9 gallons), for longer range between fill-ups. The XK has a gallon more fuel capacity than the 911 AWD’s standard fuel tank (18.7 vs. 17.7 gallons).
For better stopping power the XK’s standard brake rotors are larger than those on the 911:
XK |
911 |
|
Front Rotors |
12.8 inches |
12.52 inches |
Rear Rotors |
12.8 inches |
11.77 inches |
The XK stops shorter than the 911:
XK |
911 |
||
60 to 0 MPH |
115 feet |
116 feet |
Motor Trend |
For better traction, the XK has larger front standard tires than the 911 (245/45R18 vs. 235/40R18). The XK’s optional front tires are larger than the largest tires available on the 911 (255/35R20 vs. 235/35R19).
For better ride, handling and brake cooling the XK offers optional 20 inch wheels. The 911’s largest wheels are only 19 inches.
Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires available on the XK can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The 911 doesn’t offer run-flat tires.
The XK has a standard 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 911, it requires you to depend on roadside assistance and your vehicle will have to be towed.
The XK has vehicle speed sensitive variable-assist power steering, for low-effort parking, better control at highway speeds and during hard cornering, and a better feel of the road. The 911 doesn’t offer variable-assist power steering.
For a smoother ride and more stable handling, the XK’s wheelbase is 1 foot, 3.8 inches longer than on the 911 (108.3 vs. 92.5 inches).
For better handling and stability, the track (width between the wheels) on the XK is 2.9 inches wider in the front and 2.3 inches wider in the rear than the average track on the 911.
The XK’s front to rear weight distribution is more even (52.1% to 47.9%) than the 911’s (39.1% to 60.9%). This gives the XK more stable handling and braking.
The XK Coupe goes through Road & Track’s slalom 1 MPH faster than the 911 Turbo Carrera 4 (67.5 vs. 66.5 MPH).
For better maneuverability, the XK’s turning circle is 2.7 feet tighter than the 911’s (33.3 feet vs. 36 feet).
The XK Convertible has .5 inches more front headroom and 5 inches more front shoulder room than the 911 Cabriolet.
The XK Convertible has a much larger trunk with its top down than the 911 Cabriolet (7.1 vs. 4.8 cubic feet). The XK Convertible has a much larger trunk with its top up than the 911 Cabriolet (10 vs. 4.8 cubic feet).
With its convertible body style, valet key and remote trunk release lockout, the XK offers cargo security. The 911’s non-lockable folding seat and non-lockable remote release defeat cargo security.
Unlike the driver-only memory seat and mirrors optional at extra cost in the 911, the XK has standard driver and passenger memory, so that when drivers switch, the memory setting adjusts the driver’s seat, steering wheel position and outside mirror angle and the front passenger seat also adjusts to the new passenger’s preset preferences.
The XK’s standard easy entry system raises the steering wheel, making it easier for the driver to get in and out. The 911 doesn’t offer an easy entry system.
To help drivers avoid possible obstacles, the XK has standard cornering lights to illuminate around corners when the turn signals are activated. The 911 doesn’t offer cornering lights. The XK also offers optional adaptive headlights to illuminate around corners automatically by reading vehicle speed and steering wheel angle.
The XK’s standard dual zone air conditioning allows the driver and front passenger to choose two completely different temperatures so people with different temperature preferences won’t have to compromise. This makes both the driver and front passenger as comfortable as possible. The 911 doesn’t offer dual zone air conditioning.
To keep a safe, consistent following distance, the XK offers an optional Adaptive Cruise Control, which alters the speed of the vehicle without driver intervention. This allows the driver to use cruise control more safely without constantly having to disengage it when approaching slower traffic. The 911 doesn’t offer an adaptive cruise control.
Wireless connectivity is standard on the XK, connecting the driver and passenger’s cell phones to the vehicle systems. This allows them to use the vehicle’s stereo and hand controls to place calls safely and easily. Porsche doesn’t offer wireless connectivity on the 911.
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