By David Haueter
BMW's 3 Series is the quintessential sports sedan. Despite more and stronger competition from Mercedes, Audi, Infiniti and even Cadillac, the 3 remains the target they are all shooting for. Over the years and ongoing model generations, the 3 Series has evolved by offering just about any body style that buyers may want, including sedan, coupe, wagon, convertible and hatchback. To better compete against Audi's A4 Quattro's, BMW makes the all-wheel-drive xi models, the 325xi (in sedan or wagon) and the 330xi (sedan only).
The xi's use a version of the all-wheel drive system that's in the X5, with power split 38% front and 62% rear. In slippery conditions, power is diverted to the wheels with the greatest traction through a version of BMW's Dynamic Stability Control system, known as DSC-X. Both 5-speed manual and 5-speed automatic transmissions are available in the xi models. Most importantly, the 330xi has the same excellent 3-liter engine that's in the 330i, which delivers 225hp and does it in a linear and butter-smooth fashion. It's simply one of the best (maybe the best) 6-cylinder engine on the market today. The extra hardware in the 330xi we tested adds an extra 198-lbs in weight compared to the standard 330i, at 3,483-lbs. With that extra weight, the 330xi takes a half-second longer to get to 60mph, at 6.9-seconds vs. 6.4-seconds in the 330i. The higher ride height of the 330xi also makes it stand almost an inch taller than the 330i.