I have downloaded Kazunori Ito's Balliol.     The .air and cfg files are set up for a turboprop engine.      The RAF Balliols used the Merlin piston engine.      I have amended the .air and cfg files with the parameters of the Merlin.      Unhappily, the performance is unsatisfactory.    In particular, the achieved rpm are too low.     Is there a better way of achieving this change over?

Thank you Groundbound1.      What I have done so far is entered the appropriate Merlin parameters into the cfg and .air files.     I had no idea what to do with the prop so I just left the parameters as they were.      It's a four blader whether the power plant is turbine or piston.     I would appreciate hearing further from you.     As an aside, I once - long ago - wrote to Kazunori politely pointing out that some aircraft of his was piston powered not turbine powered and asking whether he could supply amended .air file entries.    His reply indicated that he was on the verge of apoplexy - he had no interest in .air files - and I was a very bad person.      For months, at every knock on the door, I expected the ninjas to swarm in.