IO 520 aircraft engine?

Question

Why does this engine only put out 200 to 300 plus horsepower when comparable automotive engines are producing one horsepower per cubic inch? There must be a reasonable answer to this.

Answer 1

they spin at 2500 rpm because that is when the prop is the most efficient. they all put out at least 290 depending on altitude and/or the presence of a turbo. they are industrial engines made to operate at a constant rpm for long periods of time. Cars are not required to put out full power at 5000 rpms constantly for 5 hours in a row like an airplane.

this probably doesn't answer your question but you are basically trying to compare apples to oranges.

Answer 2

The IO 520 is producing that horsepower at 2500 RPM (+/- 200 RPM or so).  Most cars get peak horsepower at 5000 to 7000 RPM.  Horsepower is torque times RPM (divided by a constant).  If an airplane engine and car engine produce about the same horsepower, the airplane engine would have to produce roughly twice the torque.

Answer 3

it's air cooled, not fuel injected and it's rpm is limited to what 3000 rpm.

Answer 4

They produce that horsepower at 2500 rpm, which is comparable to what a car engine of the same rpm would create at that same rpm, but a little lower since the compression ratio is far less, about 6:1, compared to the 11:1 of a prius.

Answer 5

Because it has more torque.

Answer 6

a 520 cc automotive engine weight do u know..

this engine produces the power at 25oo rpm..a automotive engine cant produce the same power at the same rpm..

and also with same displacement...i dont think 500cc car produsing 250hp

automotive engine use power to drive a shft to turn wheels so higher rpm are used to run the wheels thus they produces the high power coz power is amount tht finally arrives to shaft attached to engine fr driving wheels

but the aircraft engn use the powr to drive shat and turn a proppeller..the higher rpm the danger is more of tip stalling or blade stalling in air during flight and thus rpm is reduced. but the cycle timimng and fuel grade with the burning efficiency due to design gives the power required at lesser rpm.

final i want to say only that automotive engine produces hp per cc but not a 500 cc engine can produce hp of 250.