That would be US gal and true airspeed not indicated airspeed.
So 336 US gal per hour for cruise at altitude, it would be over 500 gph for take off and low level speeding, i dont think i have seen a turbine that does not guzzle the juice.
The US military built a Long Ez and studied it, Nasa have done the same so lots of good info on that plane.
From Burt Rutan who designed it-
Quote:At 8000ft altitude with 1325 lbs (max weight) the cruise optimum speed is 140 knots (161 mph) and requires 47 thrust Hp (55
BHP)
He says in the video the V8 gets 6 gph at 200 mph, at 250 mph it burns 16 gph.
I will probably go a Rotax 912 which is around 90 lbs lighter than the 0-235 lycoming, also has a lower BSFC at the required power outputs.
The V8 will make the plane overweight which will increase take off and landing speeds, not to mention questionable safety by flying faster than Vne.
Jim Price set an altitude record for non turbo piston engined aircraft in his Long ez at just over 35,000 ft.