Jaguar‘s fastest and most powerful sedan ever will be officially unveiled tomorrow during its world premiere at the Los Angeles Auto Show. Meanwhile, rumor has it that the XFR-S will be offered with a tuned version of Jaguar’s supercharged 5.0-liter V8 to produce around 550 horsepower and 510 pound-feet of torque. All of this power will be channeled through its rear wheels, most likely via the latest ZF eight-speed automatic. Anticipated 0-60 sprint times of under 5.0 seconds and a top speed of approximately 186 mph makes this the fastest sedan in the British luxury and sports car manufacturer’s history. Superficially, the new bodywork takes on more aggressive styling including a redesigned front bumper with larger vents, more prominent side skirts, a larger rear wing and generous doses of carbon fiber.