BMW has its M cars, Mercedes has AMG and now Cadillac has its V-Series. This performance-oriented line of cars got its start with the CTS-V in 2004 and has been expanding ever since. The transformation begins with the installation of an 6.0-liter V8 good for 400 horsepower and 395 pound-feet of torque. It puts its power to the rear wheels through a standard six-speed manual transmission, a limited-slip rear axle and a short 3.73-to-1 final drive ratio to optimize acceleration. An enlarged dual-exhaust system allows the driver and surrounding motorists to appreciate the full-bodied rumble of this superb V8. Sixty miles per hour comes in just 5.1 seconds. Suspension upgrades include new shock absorbers and stabilizer bars, along with 27-percent firmer spring rates compared to the standard CTS.

Under the hood, engineers installed a cross brace between the suspension towers to improve steering response and accuracy. For fade-free stopping under duress, the Cadillac CTS-V wears a full set of ventilated Brembo brakes with four-piston calipers front and rear. To ensure a tight bond to the pavement, the sedan is fitted with seven-spoke 18-inch wheels and 245/45WR18 Goodyear tires. The CTS-V comes with an adjustable stability control system that allows the driver to tailor the amount of intervention provided to his own skill level. On the cosmetic side, the CTS V-Series is distinguished by a revised front fascia with two large stainless steel mesh grilles that look sharp, while allowing for plenty of air flow to the engine compartment. In back there are twin chrome oval exhaust outlets to identify the V-Series car.

Of course, "V" logos on the deck lid, fenders, brake calipers and the speedometer do their part to slam home the message. Inside the cockpit there's a new set of instrumentation with a 180-mph speedometer, satin chrome rings around each gauge and an analog temperature gauge instead of a clock. To add to the sporty atmosphere, the three-spoke steering wheel has aluminum trim, while the door handles and shift knob get a satin chrome finish -- these additions are tasteful but the overall design is still subpar for a luxury-branded vehicle. The seats offer additional lateral bolstering to hold the driver and front passenger in place through the turns, and a lower center console armrest ensures unimpeded access to the shifter.

Although the 2006 Cadillac CTS-V can't quite match the refinement or style of European tuner sedans, it's hard not to like. Ridiculously fast in a straight line and composed in the corners, this is a car that's fast, "affordable" and fun. It shouldn't compute, but the CTS-V adds up to one of the best Cadillac cars ever.

The high-performance, four-door Cadillac CTS-V is available in one well-equipped model. Standard features include 18-inch wheels and 245/45WR18 Goodyear tires, ventilated Brembo brakes, a driver-adjustable stability control system, high-intensity discharge headlamps, leather upholstery, aluminum and chrome-finish trim, laterally bolstered sport seats, a 180-mph speedometer, dual-zone automatic climate control and a CD player. A DVD-based navigation system and a power sunroof are also standard.

For 2006, the CTS-V's V8 engine grows in displacement from 5.7 liters to 6.0 liters. This is essentially the same engine found in the Corvette. Power figures are an impressive 400 hp at 6,000 and 395 lb-ft at 4,400 rpm. Shifting through the standard six-speed manual transmission, a driver will need all of 5 seconds to reach 60 mph, and an enlarged dual-exhaust system ensures that both the driver and surrounding motorists will experience the full brunt of the V8's deep rumble.

Four-wheel ventilated discs with four-piston calipers and ABS are standard, as is a stability control system with driver-selectable levels of intervention. Also included are seat-mounted side-impact airbags for front occupants and side curtain airbags that protect front and rear occupants. In government crash tests, the CTS earned four out of five stars for driver and front-passenger protection in frontal impacts. Side-impact tests resulted in a four-star rating for front passengers and a five-star rating for rear passengers. In frontal offset crash testing conducted by the IIHS, the Cadillac car earned a "Good" rating (the best possible) and was named a "Best Pick."

The Cadillac CTS-V delivers blistering acceleration at any speed, and the standard manual gearbox provides the perfect means of enjoying it. Fast as it is, though, the sedan is subject to unnerving wheel hop during hard launches, making it seem unrefined alongside European rivals. Fortunately, the suspension displays no such flaws when it comes to keeping the car well planted on the street, where the CTS-V is every bit as entertaining as an M5. The brakes are quite strong, but inconsistent pedal feel can make them tricky to modulate. While unable to deliver performance with the cold precision of its German peers, the 2006 Cadillac CTS-V still represents one of the best blends of fun and affordability in its class.

Inside the cockpit, the standard CTS instrumentation has been swapped out for a chrome-ringed set with a 180-mph speedometer. The three-spoke steering wheel has aluminum trim, while the door handles and shift knob get a satin chrome finish -- these are nice touches, but as in the regular CTS, the overall design is awkward and materials quality is mediocre for this class. In service of the more aggressive driving a CTS V-Series owner will likely be doing, the seats offer extra lateral bolstering, and the center console armrest has been lowered for better access to the shifter. A spacious backseat allows this performance sedan to pull double duty as a family car when needed.