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Horsepower is directly related to torque calculated over time. This is why dyno's (dynometer) although show readings in HP or KW, actually measure the amount of torque the car takes to spin the rollers or hubs. (chassis dyno)

This is straight out of a history book:

The term horsepower was invented by the engineer James Watt. Watt lived from 1736 to 1819 and is most famous for his work on improving the performance of steam engines. We are also reminded of him every day when we talk about 60-watt light bulbs. The story goes that Watt was working with ponies lifting coal at a coal mine, and he wanted a way to talk about the power available from one of these animals. He found that, on average, a mine pony could do 22,000 foot-pounds of work in a minute. He then increased that number by 50 percent and pegged the measurement of horsepower at 33,000 foot-pounds of work in one minute. It is that arbitrary unit of measure that has made its way down through the centuries and now appears on your car, your lawn mower, your chain saw and even in some cases your vacuum cleaner!

POWER:

1 Horsepower = 0.7456999 kilowatts = 0.0007456999 megawatts = 745.6999 watts = 42.44498 BTU/minute = 0.7074163 BTU/second = 178.2659 calories/second = 33000 foot-pounds/minute = 550 foot-pounds/second = 76.04034 kilogram-metres/second = 1.0138712 PS (Pferdestaerke is Metric Horsepower)

There are other combinations of converting units of power, but would NEVER be used in the real world.

Example using the above:

"A Nissan R32 Skyline GTR with the twin turbo RB26DETT engine is rated @ 280PS, which equates to approximately 276BHP or 206kW."

This is why the ongoing debate of "HP versus torque - which is better?" is always such a silly thing to be talking about, since HP or KW is torque expressed over time. This why having a car that has torque being produced early and in the middle of the rpm range will always accelerate away from a car that has it's peak torque being developed higher in the rpm range despite both cars having the same HP...

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This is really serious stuff. Maybe we can turn it into an election issue, you know............ street marches, petitions, bumper stickers, politicians giving interviews on TV, all that stuff.

This could be the really BIG issue at the next Federal election horsepower or Kw, let the people decide.

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