He sounds like an interesting character, but some of his comments
contradict reality thus should be taken with a grain of salt.
He's basically saying the following:
"Low torque, high RPM engines are unreliable and have narrow
torque curves. If you give them tall gears spaced far apart, they
will not perform well." The first part is wrong, the second is
obvious but irrelevant.
That made me think, perhaps the opposite is also true, viz: "If
you take a high torque, low RPM engine, with a broad torque
curve, and give it short gears very close together, it will not
perform well."
Hmmm. . . now we have symmetric silliness.
His comments about the reliability of high RPM operation are way
off the mark. His assumption that high RPM engines can't have
flat torque curves is wrong. His failure to consider gearing is
inscrutable. Enough abstract, let's get concrete. Case in point:
two motorcycles, a Honda Magna and a Harley Davidson fat boy. The
Magna has a 10,000 RPM redline, the Harley is 5,000 RPM. The
Magna has only 50 ft. lbs. of torque. The Harley has 75 ft. lbs.
of torque. Both have five gears. The Magna is smoother, more
reliable, lasts longer, and accelerates faster at every speed.
Why? It's smoother and more reliable because it's designed
better. It has a short stroke / large bore displacement which
reduces engine stress because the pistons move slower and have
less inertia. It accelerates faster because it has more power and
less mass.
Of course the Harley sounds better but that's not T.O.O.'s
argument. . .
"Allendorfer, Peter" wrote:
>
> I don't know if you guys have seen this yet, but this guy is way cool.
> He's been around for ever and is about the smartest person I have ever read.
>
> http://www.theoldone.com/archive/world-according-1-what-is-hp.htm
> http://www.theoldone.com/archive/world-according-2-el-nino.htm
>
> -----Original Message-----
> From: Allendorfer, Peter
> To: 'Michael R. Clements '; 'Scot Zediker '
> Cc: Allendorfer, Peter; ''Dan Bratten ' '; '''Andy McKee ' ' '; '''Kit
> Wetzler ' ' '; '''Bay Area Autox ' ' '
> Sent: 1/28/00 6:09 AM
> Subject: RE: Rotary torque & noise
>
> The most power-full single engine ever, as far as I know....., is the
> Saturn 5 Rocket Booster. It's the booster that got the Apollo Moon
> shots
> off the ground. What is funny, is it was called the Power Unit, and on
> Saturn cars, the smog sticker under the hood, is labeled as Saturn Power
> Unit.
>
> -Peter
> King of Useless Info
>
> -----Original Message-----
> From: Michael R. Clements
> To: Scot Zediker
> Cc: Allendorfer, Peter; 'Dan Bratten '; ''Andy McKee ' '; ''Kit Wetzler
> ' ';
> ''Bay Area Autox ' '
> Sent: 1/27/00 3:13 PM
> Subject: Re: Rotary torque & noise
>
> Of course it's the 6000 hp that's moving the train. You can get
> that 6000 hp any way you want. The train uses 35,014 ft. lbs. at
> 900 RPM. But you could also get it with 3,500 ft. lbs. at 9,000
> RPM, or with 350 ft. lbs. at 90,000 RPM. Either way it's gobs of
> power.
>
> BTW, what's the most powerful engine made in the world? Is it the
> nuclear reactor on aircraft carriers? It takes a LOT of power to
> push a ship the size of the empire state building through the
> ocean at speeds fast enough that you could waterski off the back.
>
> Scot Zediker wrote:
> >
> > --- "Allendorfer, Peter" <Peter@regionofdoom.com>
> > wrote:
> > > Take, for example a Diesel Electric Locomotive.
> > > Say, the EMD SD-90MAC.
> > >
> > > The prime-mover (Diesel Engine) is a V-16 2-stroke
> > > Direct Injection
> > > Turbo-Diesel. It's RPM range is from 300-900. It
> > > generates 6000hp at
> > > 900rpm. Given the formula from an earlier e-mail,
> > > that would be 35013.3c
> > > lb/ft of torque. No wonder the railroads can pull
> > > mile long 8000 ton trains
> > > at speeds up to 79 mph (FRA speed limit on all Class
> > > 1 Railraods) with only
> > > 12-24 drive wheels. And steel on steel at that.
> >
> > I remember some years ago Car & Driver did a "track
> > test" of a diesel-electric locomotive. One thing they
> > said about the engine's output was that it had as much
> > torque as 65 Corvette ZR1's.
> >
> > > p.s. I have several expensive hobbies, and Model
> > > Railraods are one of them.
> > > :)
> >
> > I used to engage in this hobby myself. I'd like to
> > get back into it one of these days, when I have more
> > time and money...
> >
> > Scot
> > Do You Yahoo!?
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