list:

i have had replies pointing out that a 10 deg angle, an 18% grade, is
pretty extreme. ok, make it a 9% grade, a 5 deg angle. then 82 hp implies
2 x 22 mph = 44 mph. considering wind resistance, rolling resistance,
power for ancillary equipment, and operation below max 82 HP,
recommendation to avoid steep hills still seems reasonable. to be honest,
i haven't tried it, but i doubt tow could make much more than 20 mph even
with the 9% grade.

in any case, for the above and other saftey reasons, i would not tow a
vanagon with a vanagon except in a dire emergency.

dan

On Sun, 27 Jun 2004 14:09:54 -0400, Daniel L. Katz <katzd54@YAHOO.COM>
wrote:

>list:
>
>point is well taken. accelerating from a stop is certainly mainly a torque
>issue. and cruising on the flats the tow isn't much of a torque or
>horsepower issue, as wind resistance is not a lot higher and the extra
>rolling resistance is not a major factor (and no external force is
>required to keep the mass moving at constant speed along a straight line).
>but what about going up a hill, say 10 deg? well, 82 hp = 45,100 ftlb/s.
>assuming a combined weight of 8,000 lb, dividing power by
>8,000 lb x sin(10 deg) = 1389 lb, yields 32 ft/s = 22 mph. in other words,
>to lift 8,000 lb up a 10 deg slope at 22 mph requires the full rated 82 hp
>of a 1.9 l. since there are other losses, such as wind resistance and so
>on, and since it isn't a good idea to run an engine at full horsepower for
>long periods of time, it would seem prudent to avoid hiils.
>
>dan
>
>
>>On Jun 23, 2004, at 4:12 PM, Robert Fisher wrote:
>>
>>Semi tractor trailer trucks weigh up to 80,000 lbs and have about 300
hp..
>> A ratio of 267:1!  It's all about torque, not horsepower, when towing
>>something heavy.
>>
>>Ryan