Tranny swapability question

[Charlie Smith]

Earlier, Huw Powell wrote:
>
> > Along these same lines, any BTDT on the feasibility of adding the taller
> > fifth gear to my 84 CGT Turbo tranny? 4000rpm at 80mph is getting to be a
> > little much. My 86 4KCSQ does damn near 100mph at 4000 rpm. I would like to
> > keep 1st thru 4th gears where they are (hauls ass off the line) and use
> > fifth mainly for freeway cruising/top end. I have a spare 84 tranny I may be
> > rebuilding in the near future w/a Quaife diff and hopefully a more practical
> > fifth gear!
>
> Well, the earlier tranny (80-83) is higher geared across the board, some
> in 1-2-3 and even more in 4-5.  closer to 3k @ 80 mph as I recall.
>
> I'm supposed to be trading one of mine with Matt in Seattle who also has
> an 84 cgt and wants higher gears, as soon as I either find a suitable
> picnic chest for shipping of build a crate.  I still will have 1 or 2 of
> the higher geared fwd trannies even after that.  And I'm sure there must
> be a few out there in junkyards, too.
>
> I think you will have a tougher time just trying to lift the 5th ratio -
> one, it probably shares gears with another gear (like 4th? - anyone
> really know this stuff?), two you'll make a weird "gap" between the
> gears that might not drive "nicely."  But hey, give it a try and let us
> know how it works!
>
> Huw Powell

Somebody needs to dig into the Family Album on this.

Look for common parts like shafts and bearings to let you figure
out if it will fit.

As far as the ratio spreads, I suspect it will work fine.  I used to
gear Porsche 911 transmissions in that manner, back when I was running
stuff like a 2.0L 911S engine that was very peaky.  I'd gear the first
four gears real close with 4th maybe maxing out at 110 MPH instead of
the stock 135 MPH, and with a tall 5th gear for the road.

    - Charlie


  Charlie Smith   charlie at elektro.cmhnet.org  614-471-1418
  http://www.elektro.com/~charlie      Columbus Ohio   USA
  http://www.elektro.com/~audi     photos & technical info

  95 S6 Quattro  -  24 PSI, RS2 6 speed, and other features
  96 Dodge Ram   -  30 PSI, w/Cummins turbo diesel







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