Panther Sport Aircraft Forums

That was my point Tony, but you said it better! The little engine needs to work harder to make the same power and to answer the original question, the smaller engine in NOT more fuel efficient but it might use less fuel than a bigger one on a given airframe at a given airspeed under the same conditions.

I think a small more efficient engine like a turbo fuel injected something would be more fuel efficient than most any carbed engine...especially at altitude where the turbo and thinner air benefits it.

Joe,

No need to look at specific engines to compare fuel burn. Put a 2850 cc Corvair and a O-320 Lycoming in otherwise identical Panthers. Put them side-by-side and run the airspeed up to 150. The Corvair will be running close to WOT and the Lycoming will be loafing along. As a very general statement, they will both be making close to the same horsepower. If that's the case, they'll both be burning about the same amount of fuel. For detailed info, Google BFSC. Or read this: http://continuouswave.com/ubb/Forum4/HTML/004149.html

Tony

Hmmm a 2700cc is a roughly 165ci or about half the size of an 0-320. Best I usually get out of an 0-320 at cruise with 2450 rpm is about 6.5 gph. I suppose if you get high enough and lean to a reasonable CHT you could get close to 5.5 or 6 gph out of an 0-320. My 170 with a climb prop with an 0-300 will do 6gph or a little less at FL100 leaned and full throttle but it's not making 100hp...more like 70hp or less.

Seems like a small Suzuki or Honda with fuel injection, a turbo and a belt drive would do about as good as an 0-320 but I wonder about weight.

My 2700 Corvair/pietenpol uses 5gph at 2900rpm cruise. Friend claims to get 6gph in his longez/320 at 2700 rpm cruise. Fairly amazing for 50% more hp.

Is the Corvair inherently more fuel efficient? At a cruise speed of 150 mph would it burn less than an O-200 or O-320?

Gallons per hour like Miles per gallon is very dependent on what you are doing.

Full power you will get somewhere around 7+. Cruising around 160mph with the Panther, we saw about 6 gph, but Dan didn't really try to lean it out. Most of the time he is doing aerobatics and is running near full power.

Paul

What's the fuel burn like on the Corvair? How many gph?