All Limited Models - including the 1958 Buick Roadmaster Limited Riviera Sedan - Model 750, have a 127 1/2-in. wheelbase, the 300 horsepower of a new B-1 2000 engine, air-cooled aluminum brakes and a full complement of luxury travel features. Outstanding among these: Buick's new Flight Pitch Dynaflow, new Quadrajet Carburetor, new Miracle Ride, power windows, 6-way power seat, power brakes and power steering.