Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 60, p. 127. Works numbers were 54135 in November 1920, 54198-54208 in December.
Following the SM main-line Pacifics of the 900 class into service, these were based on the Chosen lines and had more cylinder volume, a lower boiler pressure, a larger grate, but smaller firebox with 18.3 sq ft of arch tubes. The Chosen engines also had a longer engine wheelbase, but a smaller tender.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 901 |
| Locobase ID | 13138 |
| Railroad | South Manchuria - Chosen |
| Country | Korea |
| Whyte | 4-6-2 |
| Number in Class | 12 |
| Road Numbers | 901-912 |
| Gauge | Std |
| Number Built | 12 |
| Builder | Baldwin |
| Year | 1920 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 12 / 3.66 |
| Engine Wheelbase (ft / m) | 32.33 / 9.85 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.37 |
| Overall Wheelbase (engine & tender) (ft / m) | 63.60 / 19.39 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 126,000 / 57,153 |
| Engine Weight (lbs / kg) | 207,000 / 93,894 |
| Tender Loaded Weight (lbs / kg) | 110,000 / 54,431 |
| Total Engine and Tender Weight (lbs / kg) | 317,000 / 148,325 |
| Tender Water Capacity (gals / ML) | 5500 / 22.73 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 10 / 11 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 70 / 35 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 69 / 1753 |
| Boiler Pressure (psi / kPa) | 180 / 1240 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 24" x 26" / 610x660 |
| Tractive Effort (lbs / kg) | 33,208 / 15062.91 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.79 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 168 - 2" / 51 |
| Flues (number - dia) (in / mm) | 26 - 5.375" / 137 |
| Flue/Tube length (ft / m) | 18.17 / 5.54 |
| Firebox Area (sq ft / m2) | 171.30 / 15.92 |
| Grate Area (sq ft / m2) | 47 / 4.37 |
| Evaporative Heating Surface (sq ft / m2) | 2423 / 225.19 |
| Superheating Surface (sq ft / m2) | 590 / 54.83 |
| Combined Heating Surface (sq ft / m2) | 3013 / 280.02 |
| Evaporative Heating Surface/Cylinder Volume | 177.98 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 8460 |
| Same as above plus superheater percentage | 10,152 |
| Same as above but substitute firebox area for grate area | 37,001 |
| Power L1 | 13,061 |
| Power MT | 685.58 |