"dpb" wrote in message
...
Worn Out Retread wrote:
I am looking for a new snow blower and have discovered that the power
rating of the engines are no longer in "Horse Power" but in "Foot Pounds"
if given at all. Sometimes all that is given is the CC's of the engine.

Even the people selling these machines don't know what the "Horse Power"
ratings are so that old geezers like myself can understand what is going
on. Does anyone have any general rules regarding the conversion of Foot
Pounds or CC's to Horse Power?

Unfortunately, not at all precisely, no...thanks to the dam lawyers

One can _VERY_CRUDELY_ estimate hp at about 60-70% of torque.

The relationship I recall (I'd have to go off and think again to re-derive
the denominator) of hp ~ torque (ft-lb)*rpm/5250 which boils down to the
above since most ratings are at 3200-3600 rpm.

Unfortunately, that's about best one can do other than simply try to find
similar engine w/ known rating and compare based on displacement. Problem
there is that tune and emissions requirements, etc., make that comparison
as variable as the above.

Earlier Northern Tool catalog still listed an unofficial "old hp rating"
as well but I just looked and the last one doesn't. Now I'm hoping I
didn't throw the old one away and lose that cross-reference.

All in all, it sucks to guess how to compare even worse than before when
ratings could be tweaked--at least you knew what Sears was doing w/ "peak"
or "instantaneous" horsepower; the torque ratings might be absolutely
accurate but they're still nearly useless as a comparison to previous
ratings and certainly there's not even the same measure used if only
provide displacement in one and torque in another.

--
I had an eight horse power MTD blower and for most most jobs it was
perfectly adequate. Now that I want a new blower, I don't want to buy a
machine that has less power than the old one but the published specs are
just plainly designed to confuse the buyer and there are very few web sites
that do much to untangle the mess of misleading information.

If all you are doing is clearing 6 inches of snow off a driveway that is one
thing but when the snow plough comes by and dumps a mess 2 feet deep and 6
feet up the drive, that small snow blower is just not going to get the job
done without nearly blowing its guts out especially if the material to be
cleared has had any great amount of salt added to it making the mess very
dense and therefore heavy and difficult to move.
--
Ron