Engine    
322 cu in (5.3 L) Nailhead V8

Transmission    
2-speed Dynaflow automatic

Dimensions
Wheelbase    
127.0 in (3,226 mm)
Length    
1954: 216.8 in (5,507 mm)
1955: 216.0 in (5,486 mm)
1956: 213.8 in (5,431 mm)
Width    
79.8 in (2,027 mm)
Height    
62.6 in (1,590 mm)
Curb weight    
4,400–4,600 lb (2,000–2,100 kg)

Buick Roadmaster on Wikipedia

RWD (rear-wheel drive), manual 3-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 164 kW / 220 hp / 223 PS ( SAE ), torque: 433 Nm / 319 lb-ft, 
characteristic dimensions: outside length: 5210 mm / 205.1 in, width: 1918 mm / 75.5 in, wheelbase: 3099 mm / 122 in
reference weights: shipping weight 1760 kg / 3880 lbs estimated curb weight: 1840 kg / 4060 lbs
top speed: 164 km/h (102 mph) ;
accelerations: 0- 60 mph 8.8© s; 0- 100 km/h 9.9© s ; 1/4 mile drag time (402 m) 17© s 
fuel consumption and mileage: average estimated by a-c©: 21.3 l/100km / 13.2 mpg (imp.) / 11 mpg (U.S.) / 4.7 km/l

RWD (rear-wheel drive), automatic 2-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 190 kW / 255 hp / 258 PS ( SAE ), torque: 462 Nm / 341 lb-ft, 
characteristic dimensions: outside length: 5425 mm / 213.6 in, width: 2032 mm / 80 in, wheelbase: 3226 mm / 127 in
reference weights: shipping weight 1905 kg / 4200 lbs estimated curb weight: 1990 kg / 4390 lbs
top speed: 183 km/h (114 mph) ;
accelerations: 0- 60 mph 10.6© s; 0- 100 km/h 11.1© s ; 1/4 mile drag time (402 m) 18.5© s 
fuel consumption and mileage: average estimated by a-c©: 20.9 l/100km / 13.5 mpg (imp.) / 11.3 mpg (U.S.) / 4.8 km/l

RWD (rear-wheel drive), automatic 2-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 164 kW / 220 hp / 223 PS ( SAE ), torque: 433 Nm / 319 lb-ft, 
characteristic dimensions: outside length: 5210 mm / 205.1 in, width: 1918 mm / 75.5 in, wheelbase: 3099 mm / 122 in
reference weights: shipping weight 1830 kg / 4035 lbs estimated curb weight: 1910 kg / 4210 lbs
top speed: 176 km/h (109 mph) ;
accelerations: 0- 60 mph 11.3© s; 0- 100 km/h 11.9© s ; 1/4 mile drag time (402 m) 18.9© s 
fuel consumption and mileage: average estimated by a-c©: 19.9 l/100km / 14.2 mpg (imp.) / 11.8 mpg (U.S.) / 5 km/l

RWD (rear-wheel drive), manual 3-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 132 kW / 177 hp / 180 PS ( SAE ), torque: 400 Nm / 295 lb-ft, 
characteristic dimensions: outside length: 5505 mm / 216.75 in, width: 2032 mm / 80 in, wheelbase: 3226 mm / 127 in
reference weights: shipping weight 1862 kg / 4105 lbs estimated curb weight: 1940 kg / 4280 lbs
top speed: 149 km/h (93 mph) ;
accelerations: 0- 60 mph 11.5© s; 0- 100 km/h 12.7© s ; 1/4 mile drag time (402 m) 18.6© s 
fuel consumption and mileage: average estimated by a-c©: 20.7 l/100km / 13.7 mpg (imp.) / 11.4 mpg (U.S.) / 4.8 km/l

RWD (rear-wheel drive), automatic 2-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 136 kW / 182 hp / 185 PS ( SAE ), torque: 408 Nm / 301 lb-ft, 
characteristic dimensions: outside length: 5505 mm / 216.75 in, width: 2032 mm / 80 in, wheelbase: 3226 mm / 127 in
reference weights: shipping weight 1903 kg / 4195 lbs estimated curb weight: 1980 kg / 4360 lbs
top speed: 162 km/h (101 mph) ;
accelerations: 0- 60 mph 13© s; 0- 100 km/h 14© s ; 1/4 mile drag time (402 m) 19.1© s 
fuel consumption and mileage: average estimated by a-c©: 20.3 l/100km / 13.9 mpg (imp.) / 11.6 mpg (U.S.) / 4.9 km/l

RWD (rear-wheel drive), manual 3-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 176 kW / 236 hp / 239 PS ( SAE ), torque: 447 Nm / 330 lb-ft, 
characteristic dimensions: outside length: 5250 mm / 206.7 in, width: 1935 mm / 76.2 in, wheelbase: 3099 mm / 122 in
reference weights: shipping weight 1735 kg / 3825 lbs estimated curb weight: 1820 kg / 4010 lbs
top speed: 188 km/h (117 mph) ;
accelerations: 0- 60 mph 9.1© s; 0- 100 km/h 9.5© s ; 1/4 mile drag time (402 m) 17© s 
fuel consumption and mileage: average estimated by a-c©: 19.1 l/100km / 14.8 mpg (imp.) / 12.3 mpg (U.S.) / 5.2 km/l

RWD (rear-wheel drive), automatic 2-speed gearbox
gasoline (petrol) engine with displacement: 5272 cm3 / 321.7 cui, advertised power: 176 kW / 236 hp / 239 PS ( SAE ), torque: 447 Nm / 330 lb-ft, 
characteristic dimensions: outside length: 5250 mm / 206.7 in, width: 1935 mm / 76.2 in, wheelbase: 3099 mm / 122 in
reference weights: shipping weight 1776 kg / 3915 lbs estimated curb weight: 1860 kg / 4100 lbs
top speed: 184 km/h (114 mph) ;
accelerations: 0- 60 mph 9.6© s; 0- 100 km/h 10.1© s ; 1/4 mile drag time (402 m) 17.7© s 
fuel consumption and mileage: average estimated by a-c©: 20.4 l/100km / 13.9 mpg (imp.) / 11.5 mpg (U.S.) / 4.9 km/l

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