______-miling the Jaguar XK-R

Hypermiling is too strong a phrase when you apply the MPG-increasing practice to a Jaguar XK-R. Extra-miling might pass muster, but all it amounts to in this particular instance is driving a $104,000, 420 horsepower Jaguar convertible like it's a $22,000 Camry.

Why not go for big dollops of both performance and luxury when you're trying to rock every possible mile out of a tank of fuel? With that in mind, we lined up a Jaguar XKR convertible filled to the hilt with everything but the
$8,000 brake upgrade. When it arrived, the last thing on our minds was what kind of mileage it gets. Dressed in a metallic red called "Radiance" which complemented the tan leather interior and matching cloth top, it looked like the ride home from the office was going to be a good one. Then the thunderstorms rolled in and stayed for a week. Hit the jump to see how we dealt with the weather in our XK-R.

Unfortunately, a high performance vehicle is a bit like a loose nuke when driven foolishly in the rain. Since we were doomed to a week of abject frustration behind the wheel of a restrained cat, we started dreaming up ways to make chicken salad from chicken...other stuff.

The theory is thus: it's a no-brainer to get big mileage out of little cars, but even a responsibly-driven GT should do okay. Proving that the fuel economy isn't that bad could also make the case for this type of vehicle even in the midst of a fuel crisis. Remember how musclecars were worth zilch in the seventies?



Here was this car with a wheel and tire package alone ringing up a $5,000 bill, a gnarly supercharger whine atop a tight V8 rasp, and plenty of locomotion underfoot. Rain or not, we were determined to find a way to tickle that mildly unresponsive red start button every morning. While all is not perfect in XK-land - the slow touch screen is relied on too heavily, the steering is too light, and the car can feel twitchy as those big steamroller wheels interact with scarred pavement - sliding into the classically handsome interior with aromatic leather, rich burled wood, and tasteful chrome accents is a sybaritic delight. It should be no surprise, then, that we tried to maximize our seat time in the Jaguar driving environment.

With a daily round-trip commute of roughly 50 miles serving as a test loop, we set out with a fresh fill of 93 octane and a zeroed trip odo. Sunshine finally kissed New England hillsides long enough to make the first day a top-down affair. It was also a left lane experience. Jaguars do not like to be caged. The nearly all-highway route may have contributed to the bad mileage being not that bad. After 52.5 miles, topping off took 2.853 gallons of fuel; the XKR delivered 18.401 miles per gallon.

The next morning with a once-again full tank, we set off again. The top stayed up, with the windows closed and air conditioner keeping things comfortable. We could have checked the sidewalls of the 20" tires to find the maximum inflation pressure, which would have lowered rolling resistance at the expense of the ride, though possibly benefiting handling. Don't go all Safety Patrol on us - maxing out the pressure to what's indicated on the tire itself is perfectly safe on the street.

Some hypermiling practices deliberately flout the law, so we opted to keep it legal. We did keep our foot out of the throttle as much as possible, choosing a much more sedate - yet still entirely adequate - rate of acceleration. Poking along at 65mph, treating the XK-R like you would a Sentra, is a snoozefest. The Jag wants to run, and doesn't breathe hard serving commuter duty.

When day two was all said and done, we'd covered 45.2 miles on the same basic route. Those miles were accomplished with 2.159 gallons of fuel, yielding 20.935 miles per gallon. Covering an extra 2.5 miles from every gallon of fuel isn't horrid, but we were expecting to see more contrast. So, while the XK-R isn't the poster child for efficiency, we reinforced the duh-inducing statement that driving sensibly, smoothly, and sedately will give you better fuel economy. And we had fun doing it.