Andrew Moyce wrote:
>
> I have followed the discussions about overdrives and 5-speeds with
> interest.
> My TD has a TF (1:4.875) rear end which matches nicely with the rebuilt
> and ported engine. I feel the car is at peace with itself until I get up
> above 50 mph, where I find myself reaching for a 5th gear.
> The standard solution is to "upgrade" to a 4.55 or 4.3 MGA rear end . .
> . not an uncomplicated or inexpensive proposition and with some
> compromise in low gear performance (the exent of the compromise varies
> in description from mild to significant.)
> Another solution is to change to a Datsun B-210 5-speed transmission,
> which I assume has an overdrive 5th gear. Again not inexpensive (about
> $1800) and with some philosophical drawbacks as to originality and
> honoring the Mark and all that.
> There is an outfit that makes overdrive units that are designed for
> interposing into a split driveshaft in any vehicle . . . cost about
> $1500 and concerns over whether there is room along the T car's drive
> train to accomodate the unit.
> There were some postings on the UK web site a few months back about an
> Austin Healy overdrive unit modified to fit a TD, but it hadn't been
> installed yet.
> Somewhere out there there has to be an add-on overdrive unit that we
> could adapt to the T cars . . . possibly mounted at the rear of the
> drive shaft under the storage area.
> Until I find such a thing, I am inclined to stay where I am, enjoying
> the low gear performance. I take comfort in the DuBois' experience with
> high rev motoring. I think that's how these cars were designed.
My apologies up front for jumping into something I don't have much info
about. Of course, I'm not having a problem with my ride, since it's the
Victor quasi-TF and uses MGB running gear, power-train, brakes, etc. The
highway cruising is so smooth and effortless I haven't even paid much
attention to the revs (sorry to say). What I wanted to add to the
discussion is that rolling tyre diameter is the last thing to set the
ratio of engine speed to road speed, so was wondering if somebody might
make a tad higher profile tyre that still has enough strength to keep
the handling from deteriorating? Wouldn't this help a bit?
My main area of expertise is Minis and the Mini-listers continually chew
over tyre and wheel sizes and rolling diameters and such.
-Rock
--
Rocky, JJ Cale Band & Pratchett Books: http://www.rocky-frisco.com
Rocky's Mini Cooper Page: http://www.geocities.com/MotorCity/6437/
Mini Books: http://www.geocities.com/MotorCity/6437/rockboox.html
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