Hey Scott -
The engines are Lycoming T55L7 turbines. We have them set right around 3,000 hp each. They go through BPM surface drives to a special set of Mercury Lab finished propellers. We tried a bunch of one off custom props, but the Mercs have been the best. Also, a "normal" high performance prop spins at 3500 rpm. Ours spin around 9000. Let me tell you, it's a real trip when a prop blade comes flying off at that rpm. Fuel consumption at idle is about 120 gal/hr. Also, when you fire up the engines, the exhaust temp reaches 600 deg C in about 3 seconds so when we are near a dock, people back up pretty quick.