What is "RPM"?

Question

For example: "horsepower @ RPM = 156 @ 6500"

Yes, I know what the abbreviation stands for but what is it relevance to whether or not one car is more suitable than another. Does it depend of pref. or is it something far more important?

Answer 1

Rpm stands for revolutions per minute. In other words it's how fast something spins such as crankshaft in an engine.

Answer 2

Yes it stands for revolutions per minute. If a car can go up to 10,000 RPM or 5,000 RPM it doesn't really matter. The tachometer (which shows you the RPM) is there so that you dont make the engine turn faster than it should - it helps to look at this when driving a manual transmission car.

If you're concerned about engine performance, look at things like horsepower and torque, not RPMS. A Volkswagen Jetta Diesel may show the same RPMS at 65mph on the highway as an 8 cylinder BMW 540, but they are very different vehicles with different performance levels.

Answer 3

Your example: For example: "horsepower @ RPM = 156 @ 6500"
Means at 6,500 revolutions per minute, or 108 1/3 Revs per Second your engine is producing 156 Horsepower. Horsepower was first a unit of measure of how much work a horse could do per minute. John Smeaton figured a horse could produce 22,916 foot pounds per minute. John Desaguliers increased that to 27,500 ft.lbs. per min. In 1782 James Watt found that a 'brewery' horse could produce 32,400 ft.lbs. per minute. Ultimately HP is Eq. to Power Eq. Work/Time Eq. ForcexDistance/Time Eq. (180lbf) (2.4x(2pi)x12 ft)/one minute Eq. 32,572(ft.lbf)/minute.

You have added another question: The 'relevance' is that the higher the RPM an engine has to turn for a given speed, the faster it will fail. Engines can turn just so many millions of revolutions and sooner or later will fail. Also you will get less miles per gallon the more HP an engine makes.

Answer 4

RPM=Revolutions per minute

Answer 5

Revolutions
Per
Minute

Answer 6

revolutions per minute