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chart for lbs -> HP (BMW owners are optimistic)



Kwattro wrote:
> ...7 pounds was equivilent to 1 hp.  IE, a car that was 70 lbs

glenahan@notes.cc.bellcore.com wrote:
> Let's do some math.  We'll assume a 2500 lb auto with a 1-HP motor.


Let's do some more math. Since weight/hp is the important result,
first let's look for the conditions when 7lbs = 1hp
weight = W	HP = H

(W-7)	    W
------  = -----
  H	  (H+1)

WH-7H+W-7 = WH
W-7 = 7H

Therefore, for a 3507 lb car this generalization works if it
has 500 hp, thus proving the fact that BMW guys think they
have more horsepower than they really do.

Now, for a more realistic example, let's take a car with
3015 lbs and 200 hp.

(3015-15)	 3015
--------   = 	------
  200		(200+1)

So, it really depends on where you are starting from, but
it looks like for most of us, it'll take quite a bit more
than 7 lbs to equal 1 hp.

On my 83urq (see urqmonster posts)
3010scale-70a/c removed + 180 me = 3120 lbs
306hp (GTech Pro) so probably realy 270 hp
Therefore between 11-12 lbs = 1 hp

Glenn :-)