DETROIT (Jan. 6)—BMW A.G. will equip its 2004 Rolls Royce Phantom with Groupe Michelin's Pax run-flat tire-wheel system as standard equipment when the car reaches dealer showrooms in April. The Phantom is the first Rolls Royce designed and built by BMW since the German car maker bought the rights to the Rolls Royce name in 1998. It was unable to use the name until now, however. The 19-foot long, 5-foot high, 5,577-pound Phantom rides on 21.6-inch Pax rims. The launch of the Phantom marks the first standard Pax fitment for a car available in North America, Michelin said.