Under the hood is a supercharged DOHC 4.0-liter V8 engine. In normally aspirated form, this engine produces 290 horsepower, which isn't bad. Put the blower on it and horsepower increases to 370, making the XJR a car that leaps off the starting line. Acceleration is phenomenal. All this is accomplished while you're sitting in absolute luxury.
Power reaches the rear wheels through a five-speed automatic transmission.
Essentially this replaces the sequential touch-shift gearboxes that are so rife in other vehicles these days. Some thought must be put into which gear you want in this case, but then you should put some thought into your shifting anyway. The advantage is that you can upshift or downshift two gear levels, which you can't do in the sequential shifters. I had an opportunity to drive the XJR at Pocono Raceway on the road course, shifting all the way. This makes the XJR a pleasant car to drive as well.