Hi GDex.

I'm not trying to detract from what Michael has done, but all I did to improve the performance of the 727-200 was to increase its static_thrust. Here is what I change it to:

[TurbineEngineData]
fuel_flow_gain= 0.003
inlet_area= 18.000
rated_N2_rpm= 29920.000
static_thrust=17400     //15500
afterburner_available= 0
reverser_available= 1
ThrustSpecificFuelConsumption = 1
AfterBurnThrustSpecificFuelConsumption = 0

I increased it from 15500, which is the same as static_thrust as the 727-200.

The reason I chose 17400 comes from find this: Eight models comprise the JT8D standard engine family, covering the thrust range from 12,250 to 17,400 pounds-force (62 to 77kN) and power 727, 737-100/200, and DC-9 aircraft. on wikipedia. I couldn't find specific thrust for specific engines. I simply did not want to waste a lot of time searching it out. I wanted to fly it. Making that simple change has improved the climbing ability of the 727-200 immensely. Mine climbs to FL350 quite easily now.

Mark