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novanutcase
11-25-2006, 10:59 PM
I was wondering if anyone can tell me how many pounds will 1 horsepower move and how that relates to the weight of our cars versus the horses we put under the hood!

Thanks!

John

68sixspeed
11-26-2006, 07:01 AM
1hp= the work or power needed to lift 550 lbs vertically 1ft in one second. This was what was established years ago as the work one horse could do in a minute.

1hp can move almost anything, with enough gear ratio or reduction.-- if you've ever winched a car/truck you've moved it with only a few hp max. Now what happens when the winch isn't strong enough?- you use a snatch block to double the linear pull, but it takes twice the distance.

Correct me if I'm wrong, but I think what you are getting at is how much hp does it take to get to a given speed in a given distance? For that, the old Moroso slide charts is a great tool for what-ifs. I use to have the formula for doing it yourself handy, but I can't find it right now- perhaps someone else can post it, but basically it related hp to weight and a constant to achieve a given mph in the 1/4 mile.

Some homework-- http://www.edmunds.com/ownership/techcenter/articles/43845/article.html

Damn True
11-26-2006, 11:49 AM
1 hp is also 746.7 watts (Watt was also the guy who came up with the term "horsepower" and the "watts" link)

also

1 hp is 2545 BTU

and

1 hp is 26.8 Million joules

and

https://static1.pt-content.com/images/pt/2006/11/cc84084a478f3bc9ff99a5dd9374f6b1-1.png

Fuelie Fan
11-27-2006, 08:37 AM
BTUs and joules are units of energy, not power. I think you also misplaced a decimal.

1hp = 2544.4 BTU/hr
1hp = 2.68 million joules/hr