Supercharging the $100,000 Cadillac XLR meant adding a new 4.4-liter version of the Northstar V8, the same powerplant that’s rocking the STS-V. However, because of the XLR’s reduced hood clearance, it makes 443 horsepower and 414 lb.-ft. of torque in this roadster. Peak torque is spread across a plateau in the powerband that runs from 2,200 to 6,000 rpm, ensuring a 4.6-second acceleration time to 60 mph.