Zvezda M503

The Zvezda M503 was a maritime 6 row, 42 cylinder diesel radial engine built in the 1970s by the Soviet Union. Its primary use was in Soviet missile boats, that used three of these engines.

This engine may have had other applications, but due to its extreme weight (12,000 lb (5,400 kg)), it would have been limited to ground or naval applications.

A German tractor pulling team designed a vehicle around a methanol-fueled version of this engine,^[1] this modified^[2] engine is said to weigh 3,200 kg (7,100 lb) including the gearbox, for use in the 5.4 ton tractor pulling class, making 8,000 hp (6,000 kW) at 2,500 rpm.

Specifications (Zvezda M503A)

General characteristics

• Type: 42-cylinder Liquid cooled 6 row, 7 cylinder per row diesel radial engine
• Bore: 6.29 in (160 mm)
• Stroke: 6.69 in (170 mm)
• Displacement: 8,763 in³ (143.6 L)
• Length: 145.66 in (3,700 mm)
• Diameter: 61.41 in (1,560 mm)
• Dry weight: 12,015 lb (5,450 kg) (dry)

Components

• Valvetrain: 7 overhead cam shafts, one per bank.
• Fuel type: Diesel fuel
• Cooling system: Liquid-cooled

Performance

• Power output: 3,942 hp (2,940 kW, 3,997 PS) at 2,200 rpm
• Specific power: 0.44 hp/in³ (20.47 kW/L)
• Power-to-weight ratio: 0.32 hp/lb (0.53 kW/kg)

Comparable engines

• Napier Deltic

References

Translated from : German Wikipedia