Jon
I was told some years ago that when hypoid axle ratios fall below 3.00:1 the
efficiency drops dramatically, so car manufacturers try to stay above 3.00:1
whenever they can. That is why Chrysler introduced an overdrive rather then
go to a rear axle ratio lower then 3.00:1 back in the seventies. That is also
possibly the reason for the O/D on the early Healey's.
Jan
"jon" <humber_snipe@hotmail.com> wrote:
My guess is they didn't have a low enough (numerically) ratio gearset for
the rear axle, so rather than design a whole new differential assembly, they
just used what they had on hand. If they had used a tall axle ratio like
2.54 to 1, they could have used the granny low. However, I think it wasn't
synchronised. By blocking off low, they could then claim an all-synchro
gearbox.
Humber used three speed manual trannies in the Series Super Snipes. They
felt the torque was adequate, and adding a fourth gear was useless.
Overdrive was an option, though, and makes a Super Snipe a very happy
cruiser at 75mph on modern highways.
Jon Arzt
----- Original Message -----
From: "Jan Eyerman" <jan.eyerman@usa.net>
To: "Matthew Trebelhorn" <matttrebelhorn@netscape.net>;
<jan.eyerman@usa.net>
Cc: <bmounce@bellatlantic.net>; <ian@sunbeamalpine.org>;
<the_blues@worldnet.att.net>; <v.hughes@student.canberra.edu.au>;
<alpines@autox.team.net>
Sent: Tuesday, March 06, 2001 12:31 PM
Subject: Re: [Re: [Re: [Was now what to do with it.]]]
> I have heard the same thing, but it doesn't make sense.... why would they
do
> that and then add overdrive???
>
> Jan
>
>
>
> matttrebelhorn@netscape.net (Matthew Trebelhorn) wrote:
> Actually, they were 4-speeds with the "stump-puller" first blocked off.
>
> Or so I'm told.
>
> Matt
>
>
> Jan Eyerman <jan.eyerman@usa.net> wrote:
> >
> > The early Austin Healey 100's (with the 4 cyl engine) probably had
> overdrive
> > as they only had 3 speed transmissions.
> >
> > Jan
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