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Gunner[_2_] Gunner[_2_] is offline
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Default Why use heavy oils in gearbox?

On Sun, 23 Dec 2007 08:26:52 GMT, Ted Frater
wrote:

Don Young wrote:
"RAM³" wrote in message
0...

"Ivan Vegvary" wrote in news:yPUaj.12$ML6.5@trndny04:


which makes me wonder, why
we use heavy gear oils for similar applications when not unitized with
an automatic tranny?

The '62 MG Midget that I once had used 30-wt. motor oil in its 4-speed
manual transmission.


For what it's worth, the late 40's Chrysler electro/vacuum shifted
transmission used 10 weight motor oil to lubricate conventional gears.

Don Young



This busines of 35mpg is quite simple to acieve.

The technology is there,
It needs a tax? incentive for the car MFG's
to change their design references.
So lets look at these.

1.
a steady state speed on a straight level road,
take any one it doesnt matter.
the energy needed to keep the car at this speed is equal to the drag.
this is from several areas.
rolling resistance,
engine/transmission friction losses,
engine efficiency
aerodynamic drag.
Each one can be optimised with current technology.

Next,
2.
accelerating from one speed to another, this could be from 0mph to
30mph or whatever.
This requires the engine to accelerate the total mass of the car.
the enegy needed to do this is primarily dependent on the the time you
want to do this in and the weight, in addition to 1. above

The former is in the control of the driver and the second is again in
the hands of the maker..

So if you want to optimise your car for maximum miles per gallon it will
need to be

very light,
all aluminium , composite construction
very aerodynamic
very low rolling resistance, no soft sqiggy tyres
ie throw away your fancy wide fashion
statment tyres
and run on the old design michelin"X" as made in the 1960's
super effient turbocharged common rail pulsed fuel injection diesel
aka VW polo or Smart car
all aluminium engine transmission castings,
lightweight glass in windows,

made in 2 seat tandem configuration ,
as well as 4 seat and larger.

With these specs I predict at a steady state speed of 70 mph a mpg on US
gallon of over 70. with current technology,
Give me the authority and funding and ill have one ready for mass
priduction for you in 24 months.

Any takers?
Ted Frater
Dorset UK.





Now the next question, will the occupants survive a collision with
anything larger than an opossum?

Gunner