Re: Diff swapping and percived performance

[George & Cathleen Ax <axes@xxxxxxxxx>]

This sounds convincing.  I checked my relatively recently-purchased '88
535i last weekend, and it doesn't have a LSD (in case anyone was still
wondering whether all '88's had LSD ... they don't).  Can anyone tell me
where to get a 3.73 LSD?  Which, if any, BMW has this differential?  Thanks!

>   Having swapped numerous diffs(final drive ratio's, ring pinion gears) in a
>variety of cars from VW to P cars ( not easy ) you do change the shift point.
>But it will also effect how the car performs. Take a  E28 535 with a 3.25 diff
>max speed is around 134-136, last time I checked in fourth gear, car will
>probably not be able to pull to the redline because of drag/hp(this is  with a
>chip). Take the same car put a 3.73 diff in and fourth gear will now pull
>clean to the limiter@125mph 6,600rpm. And it will  pull in fifth. And it does
>accelerate a bit faster.
>    Now take the cars to a road/ drag, course/strip and run the donkey out of
>both taking timed laps/runs....swap the diffs and see which one is
>faster...The 3.73 will be several seconds faster because it can put the power
>to the ground more efficiently. The car will be able to accelerate out of the
>corners better because of the gearing change.  Races are won by seconds
>sometimes tenths of a second. On the street it will feel like a new car "like
>instant HP".
>  Most Manufacturers use tall gearing to meet the MPG  laws put out by the
>government. Don't meet the laws set guideline... get a BIG mother of a
>fine.....Take the corvette  six speed that goes from second to fourth, last
>time I checked that didn't make for real good performance...
>
>  Been there done it a few times. Its why most racers and hot rod junkies swap
>out there final drive gear sets(diffs in a BMW)...goes for Mustangs, BMW's,
>Honda's, etc....
>
>Ggray
>87 535is turbo, 3.73 diff
>88 M3 Club racer, soon to have a 4.45 gear set.


o/______\o    AxMan
(oo_OO_oo)   '88 535i
[]o----o[]   115K miles, soon-to-be-sharked

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