Sorry for the delay in response, however, my mail server decided to smoke a
few parts.
> >Bryan Loy wrote:
> > I don't have the ele. od. option on my car, so I'm
> >running at a pretty high rpm lvl at interstate speeds.(4500@
> >70mph.)
>
> Trevor Jordan:
> This sounds wrong. It should be about 3500 to 3600 at 70 mph. Tachometer
> may need recalibration.
>
Trevor is correct it should be about 3500 rpm give or take.
> >Overdrive - either unit can in theory fit any car but I would stick with
> >what was normally fitted to avoid installation problems.
> >If your car has a commission number before CF/CR1 use an A-type. Works in
> >all forward gears giving you an 8 speed tranny and an 18% reduction in
> rpm
>
> Trevor Jordan:
> Works in 2nd, 3rd and 4th, but not 1st. Not really 7 forward gears: OD
> 3rd
> and 4th are very close. You can drive around the suburbs in 3rd and OD
> 3rd
> and on the highways in 4th and OD 4th without changing gears as often.
>
Oops! Shows you what I know about the A type OD. You get 7 forward gears but
the overlap may make some of these redundant.
> >When converting from a non OD to a OD tranny you must replace the main
> shaft
> >and you might as well rebuild the whole unit once you have it out.
> >Cost is about $1000 to $2500 depending on the work performed and required
> >parts (countershaft 1st & reverse gear alone is over $200).
>
> No mention of the Toyota Supra 5 speed conversion?
>
Thanks for reminding me. This appears to be the ideal solution to both the
overdrive and the weak layshaft problems. The Supra gearbox comes in a
number of different ratios:
3.27 1.96 1.31 1.0 0.775 Supra close ratio high 5th (impossible to obtain)
3.56 2.05 1.38 1 0.85 Supra wide ratio (standard)
3.28 1.89 1.27 1 0.86 Supra close ratio (optional, $180 extra cost)
3.14 2.01 1.33 1 0.797 Triumph with J type 1-4 and 4OD
I instantly tried to obtain the close ratio with high 5th which would be an
ideal replacement. Unfortunately as of 6/98 it is "very rare and not
available at present".
The sales brochure states "Supra Gearboxes are ex-Japan, cleaned and checked
over before leaving the factory". I asked what "cleaned and checked over"
involved and received the answer that "the gearboxes are scrubbed clean
(outside) ready for assembly into the car ... (the gearbox is) inspected
inside for broken gear teeth, cleanliness, shifter mechanism wears, and if
so parts are replaced".
At this point I'm wondering why I would want to pay for shipping of a
tranny, why not get one here since the tranny overhaul appears to be
minimal. For starters most of the cost is in the bell housing and not in the
transmission. The total cost is $2800 Nz which is about $1400 US at the
current exchange rate. The tranny is only $780 Nz and that includes the
optional close ratio gearbox. Still $1000 US plus cost of a used
differential is still cheaper than a TR6 overdrive, except for the fact that
the Supra shift lever is in the wrong place and must be relocated. Combined
with the fact that the speedo cable is custom built, there is no boot for
the throwout arm, it's a long drive to the customer service department (New
Zealand), and no one on the net had any experience that they wanted to share
about this tranny I decided to blow off it off.
Had I known that my layshaft was toasted (but still not making noise) in my
transmission I most likely would have decided to have gone the Supra route.
Jerico racing transmissions would be the ultimate tranny if it were not for
two problems: A four speed trany costs $3195 US and the final gear ratio in
4th is 1:1, so much for overdrive.
Just for information I did decide to get a J type overdrive installed on the
spur of the moment when I found someone locally who I trust a lot and would
do a complete rebuild of my tranny and the overdrive and guarantee the work
for 12 months with unlimited miles.
Later
Lee
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