its basically how powerfull your turbocharger will be...I believe the lower the min_design_mp is and higher the max_design_mp is the more powerful your turbo will be...i think. Pick the standard cessna 208 grand caravans aircraft cfg and copy the turbo over from it...that should do for flying in the rockies
Remember the Cessna 208 is a
Turbo-prop aircraft with a turbine engine driving the propeller
Not a
Piston prop aircraft with a turbo-charged reciprocating piston engine turning the propeller....

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Paul...I hate Turbo-Props...

...LOL...

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A turbo-charger is is a belt driven, or exhaust driven air compressor fitted to a standard piston engine to force air under pressure into the manifold air intake to increase the engine's efficiency and therefore it's horse-power...
...it's done on motor car engines...

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