[California Saab Tuner]

Here's an interesting bit on the origins of horsepower, it was on a documentary I saw a while back:

Back in the Donkey driven coal mining days where donkeys and horses were used (well not horses so much, so it should be Donkey power) to bring up the carts and buckets of coal from the mine, it was determined that one horse could lift roughly 550 lbs straight vertical out of a mine shaft at a rate of 1 foot per second. Later on when machines where replacing horses they needed a measurement for the machines to give buyers some idea how much power the machine had to lift coal. Of course the logical solution was to sell them with power ratings based on the number of horses (donkeys) each machine lift or cart could replace. Some of the story has been fudged over the years and there are no exact times or dates for when the term was first coined, but it has since been adopted as the standard unit of automobile power measurement for over 100 years in several of the worlds largest countries.

Some interesting stuff:
1 horsepower can lift 550 lbs at 1g (vertical) at a rate of 1 fps:
1hp = 550lbs x 1g x 1 fps / 550


1 horsepower can move 550 lbs up a 10% grade at 10 fps:
1hp = 550lbs x .1g x 10fps /550

Also:
1hp = 760 Watts

This means one Hirsch upgraded 900 can light up at LEAST one thousand five hundred twenty 100 watt lightbulbs @ 200 wheel hp. Maybe I should hook the Viggen up to the Christmas lights, no? LOL

 

[Alex_S]

To confuse matters though there is also a metric 'horsepower' the PS which is 98.6% of the size the 550lbfs definition.

 

[Mark B]

550 lb.ft/s
= 550 x 9.8067/2.2046 N.ft/s
= 550 x 9.8067 x 0.3048/2.2046 Nm/s
= 746 Nm/s
= 746 W

the following conversions were used:

1kg = 2.2046lb (approx)
1kg = 9.8067N (approx)
1ft = 0.3048m (exact)

 

[California Saab Tuner]

Speaking of horsepower. *insert seriously evil grin here* I'm trying to talk one of my friends into loaning me the money for a Dyno run. He really loves the Viggen and is sort of curious himself. Plus he has $1500 just "lying" around.

Damn him! Wait no ... bless his heart. Now if I can just get him to share just a teeny little itty bitty tiny bit of that ... *ponders* If he says yes expect dyno results in the near future.

 

[Skiddins]

From HowStuffWorks.com

Definition

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!

Skiddins

 

[California Saab Tuner]

Yes indeed t'was Mr Watt.

"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." ---

Trouble is that a number of other people had come up with measurements for the same thing. None had put as much effort into making it a standard system of measure though. Kudos to Watt.