title: Walter Bora
text: # Walter Bora
  
  The Walter Bora was a Czechoslovakian nine-cylinder, air-cooled radial engine for powering light aircraft that was developed in the 1930s by Walter Aircraft Engines.
  
  ## Variants
  
  ### Bora II
  
      Direct drive engine
  
  ### Bora II-R
  
      Geared engine, reduction ratio 0.666:1
  
  ## Applications
  
  * Aero A.200
  * Nardi FN.305
  * RWD-9
  * SIAI-Marchetti SM.101
  
  ## Engines on display
  
  A preserved example of the Walter Bora engine is on display at the following museum:
  
  * Prague Aviation Museum, Kbely
  
  ## Specifications (Bora II-R)
  
  Data from Flight
  
  ### General characteristics
  
  * Type: 9-cylinder radial piston engine
  * Bore: 105 mm (4.1 in)
  * Stroke: 120 mm (4.7 in)
  * Dry weight: 172 kg (379 lb)
  
  ### Components
  
  * Valvetrain: One intake and one exhaust valve per cylinder
  * Fuel system: Carburettor
  * Fuel type: Petrol
  * Cooling system: Air-cooled
  
  ### Performance
  
  * Power output: 183 kW (245 hp) at 2,400 rpm
  * Compression ratio: 6.3:1
  * Power-to-weight ratio: 1 kW/kg (0.65 hp/lb)
  