Re: Mercedes question

[Matt Haas <mhaas@xxxxxxx>]

At 09:47 AM 8/26/2005 -0400, you wrote:
> " From: Matt Haas <mhaas@xxxxxxx>
> "
> " Fuel efficiency is why they're going with large numbers of gears in
> " automatic transmissions. The goal is to keep the engine at peak efficiency
> " as much as possible (which makes me wonder why CVT transmissions haven't
> " caught on).
>
> belt/pulley cvts are very hard to engineer for capacity, and if the
> belts are rubber, for efficiency.  i don't know about hydrostatic
> transmissions except they require extremely tight tolerances, and that
> means expense - and then there's the plumbing, and maintenance.
> electric transmisison has potential, especially in combination with
> batteries, but i think weight is still a problem.
>
> hydrostatic and electric do have interesting possibilities for all
> wheel drive.

But with a hydrostatic transmission, you really could have stump pulling 
torque!

For those who don't know hydrostatic transmissions are run off of 
hydraulics. They're used in things like Bobcats and tractors. The lawn 
tractor I bought last fall has one of these transmissions and it will go 
from nothing to top speed (7.5 miles per hour -- weeee!) fast enough to 
chirp both rear tires on clean dry pavement. I don't know if I'd really 
want one in a car due to noise (it sounds like the power steering on an old 
Ford pickup) but the instant torque is a blast.

Matt


mhaas@xxxxxxx
Cincinnati, OH
http://www.mattsoldcars.com
1967 Rambler American wagon
1968 Rambler American sedan
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