Data from A[nthony] E[dward] Durrant, The steam locomotives of Eastern Europe (Abbot Newton: David & Charles, 1966),, pp. 39, 40; "M-V series 303" in Wikipedia at [], last accessed 18 December 2021; and H le Fleming in Ransome-Wallis (1959).
One of this class was the 6,000th engine delivered by the Mavag works. The class used mechanical stokers. Rating was 500-ton passenger trains at speeds up to 120 kph (75 mph). They were big, strong, and unsuited to Hungarian railroad express requirements.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 303 |
| Locobase ID | 1553 |
| Railroad | Magyar Allamvasutak (MAV) |
| Country | Hungary |
| Whyte | 4-6-4 |
| Number in Class | 2 |
| Road Numbers | 303.001-002 |
| Gauge | Std |
| Number Built | 2 |
| Builder | MAVAG |
| Year | 1950 |
| Valve Gear | Heusinger |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | |
| Engine Wheelbase (ft / m) | |
| Ratio of driving wheelbase to overall engine wheelbase | |
| Overall Wheelbase (engine & tender) (ft / m) | 34.78 / 10.60 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 38,140 / 17,300 |
| Weight on Drivers (lbs / kg) | 115,743 / 52,500 |
| Engine Weight (lbs / kg) | 263,452 / 119,500 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 6600 / 25 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 14.30 / 13 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 64 / 32 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 78.70 / 2000 |
| Boiler Pressure (psi / kPa) | 261.10 / 1800 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 21.65" x 27.56" / 550x700 |
| Tractive Effort (lbs / kg) | 36,429 / 16523.94 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.18 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | |
| Grate Area (sq ft / m2) | 59.20 / 5.50 |
| Evaporative Heating Surface (sq ft / m2) | 2799 / 260 |
| Superheating Surface (sq ft / m2) | 840 / 78 |
| Combined Heating Surface (sq ft / m2) | 3639 / 338 |
| Evaporative Heating Surface/Cylinder Volume | 238.36 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 15,457 |
| Same as above plus superheater percentage | 19,012 |
| Same as above but substitute firebox area for grate area | |
| Power L1 | |
| Power MT | |