Dave:
You may be correct in saying that driving all day at 4200 rpm wont damage
anything. But in a TD (@about14mph per 1000 rpm) you are going only 58.8
mph. I feel safer going 68 mph on the interstates--I wont fall asleep!
Mark Sherman
----- Original Message -----
From: Dave and Liz DuBois <ddubois@sinclair.net>
To: <mg-t@Autox.Team.Net>
Sent: Thursday, January 07, 1999 4:00 PM
Subject: Re: 5 speed question
> I don't often jump into these discussions, however I think I will join
this
>one. Bob Howard and Lew Palmer are absolutely correct. An overdrive is
either
>an add on unit or a gear ratio in the gear box, achieved with extra gears
(ie. 5
>speed or 6 speed) that gives a final ratio lower than 1:1 at the input to
the
>rear axle. A lowered gear ratio in the rear axle is just that, a lower
rear
>axle gear ratio and affects the MPH/REV in each of the gear box's position.
>There are trucks in use (or used to be) that have two speed rear axles
that are
>controlled from the gear shift lever, but they are termed just that, two
speed
>rear axle as opposed to overdrive.
>
> Not to get into an argument with Lew, but I believe that the statement
"The
>second problem is that with a 1:1 ration in top gear, the engine is running
at
>much too high an RPM for comfortable cruising at 60 - 65 MPH" is a
subjective
>assessment, based on the American preference for large displacement low
revving
>engines. My wife and I have twice taken our TD, with standard gearing on
5000+
>mile trips in the Western USA, traveling 8 to 10 hrs a day at 4200 RPM and
the
>worst problem that we had was a fouled plug at the end of the last trip.
The
>high RPM did not in any way damage the engine (other than to wear it
faster),
>although I do admit to wishing for an overdrive just to make ME feel
better.
>
> Hope that this doesn't muddy the waters too much.
>
>Sincerely,
>Dave DuBois
>
>
>
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