Yep , I understand confidential information
All gas turbine freepower turbine wheels can create maximum torque at nil rpm , generally ~ twice max rpm torque , the maximum total pressure that my bikes freepower turbine experiences is ~12psit , this is a mix of several psi of static pressure and the rest dynamic pressure inherent in the high velocity gases, the bike produced 115 rear wheel horsepower , so lets say 120shp at the turbine wheel whilst running ~33,000 rpm with a mass flow of ~1.8 lbs/sec , 120hp at 33,000 rpm represents ~19 ft/lbs of torque at the turbine wheel , this would have been roughly doubled at nil freepower rpm with the gas producer at full power , so lets say 38 ft/lbs at the turb shaft , multiply that by the bikes overall gearing of 18.56:1 and we have ~700 ft lbs of torque at the rear wheel to accelerate some 830 lbs of bike and rider http://www.youtube.com/watch?v=P-5PgWqgIJo
Most turbocharged auto engines run exhaust manifold pressure up to around twice the inlet manifold pressure during hard acceleration.
You have to do your turbine calculations using total pressures and temperatures in absolute terms , so your turbine inlet pressure will be a combination of static and dynamic forces .
If you're keen on using steam turbines , may I suggest you get a copy of this book .........ISBN 1 85761 075 X Tee Publishing in the UK, book is called Model Steam Turbines by H H Harrison , just a small book of ~60 pages but very enlightening