Jaguar's 2010 XK comes in a coupe and a convertible model, each with either the naturally aspirated 5.0 liter V8 or the supercharged 5.0 liter V8 engine. The standard model engine gets an average 19 mpg in the coupe and 18 mpg in the convertible while the supercharged 5.0 V8 engine averages 17 mpg in both the coupe and convertible models. These engines are new for the 2010 lineup
Customer complaints of the older XKs being underpowered are addressed in the 2010 model by replacing the old 300 horsepower engine with the new 5.0 liter 385 horsepower engine. This new direct injected V8 serves up more power than other cars in its class, generating more excitement over the XK than it has had in years. The supercharged version offers improvements to, bumping up power from a mere 410 horsepower in previous years to 510 horsepower in the new engine. This engine also produces more torque than others in its class: 380 foot pounds at 3,500 rpm for the standard version and 461 foot pounds at 2,500 rpm " 5,500 rpm for the supercharged version. The XKs 5.0 liter engine is made with a 92.5 mm bore and a 93 mm stroke. The compression ratio for the supercharged model is 9.5 to 1 while the standard engine has a compression ratio of 11.5 to 1.
Gas mileage for the XK coupe is the best of the XK line at an average of 19 mpg (16 mpg city, 24 mpg highway). The XK convertible is rated 16 mpg for city driving and 22 mpg on the highway for a combined 18mpg. The supercharged version of this engine produces an average of 17 mpg for both the coupe and convertible.