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Truman wrote: "Where did you get those numbers?"

Hello Truman,
I used an online horsepower calculator for vehicles

http://www.gordon-glasgow.org/hpcalc.html to get the base hp for
1200lbs at an average speed of 50mi/8hrs=6.25mph with an et of
8hrs/50mi=.04hrs/.25mi(1/4mi)=144sec. Very crude and the answer is
rounded off to 0.1HP. Then I went to an online power conversion
table 

http://www.gordonengland.co.uk/conversion/power.htm and put 0.1 in
the box for horsepower(550ftlbs) and got
(1068cal/min)x(60min)x(8hrs)=512,640
calories which I rounded off to 510,000 calories. Then I tried using the
horsepower calculator for 50mi/7hrs=7.14mph and an et of
7hrs/50mi=.035hrs/.25mi(1/4mi)=126sec. but the answer was the same .1HP
because of rounding. So I used 20,000lbs and both sets of speeds to find
.9hp and 1.3hp so I assumed (very crude) that this ratio would be true
(.9hp/1.3hp)=(.10hp/.15hp) so my hp for 7.14mph and 126sec is .15HP which
I put in the power conversion table and got
(1603cal/min)x(60min)x(7hrs)=673,260
calories which I rounded off to 670,000 calories. Now to find the weight
necessary to generate 670,000cal in 8hrs over 50mi. Both online
calculators show a direct proportional change between weight to HP on one
and HP to calories on the other so 510,000cal to 670,000cal is 31% and I
made a mistake here with my calculator. (1200lbs)x(1.31)=1572lbs  I
hit (1200lbs)x(1.21)=1452lbs which I rounded off to 1450lbs so it
looks even more staggering. Can you help me out here? I think I gave
myself a headache....
Don Huston