016 transmission puzzle

["Dave Eaton" <Dave.Eaton@clear.net.nz>]

so, its raining outside, i've tidied up my tools, and i've got too much time
on my hands, but...

i've been looking at the fiche for the fabled 016 transmission and i've
noticed some differences between ekta and the fiche, and a puzzle about
ratios....

as you probably know, the 016 transmission has the input shaft (from the
clutch) with 1st and 2nd gears integrated and 3rd, 4th and 5th floating,
while the output shaft has 3rd and 4th integrated and the 1st, 2nd and 5th
gears floating.

first, there is a difference between ekta and the fiche in that ekta does
not mention different input driveshafts for the pre- and post- torsen
transmissions (note: excluding the "aae" sport q transmission, the torsen
transmissions are the "a" series transmissions: apx, asx, auh, auk and avc,
while the pre-torsen transmissions are the ug, 4h, 5h and 7z).  ekta only
specifies the 016-311-105-am input shaft, while the fiche lists the "n"
suffix for pre-september 1985 transmissions.  why is this important?  well,
the thick plottens...

according to both ekta and the fiche, the later transmissions (asx, auk and
avc) share input shaft (floating) gear part numbers with the pre-spetember
'83 transmissions (early ug, 4h and 5h)???  the late ug, 4h and 5h
transmissions (ie. 1/9/83 to 31/7/89) have different part numbers for the
floating gears, while, although the asx, auk and avc transmissions gears'
are separately listed, they have the *same* part numbers as the early
transmissions (eg. 088-311-351a 4th gear for ug, 4h, and 5h, 016-311-351b
for late 4h, 5h, 7z and apx and auh, and 088-311-351a again for asx, auk,
and avc transmissions!!!)

now the output shaft (with 3rd and 4th integrated) changed between pre-and
post- november '83, with the asx and auk transmissions listed separately but
with the same part number as the early (pre-nov '83) transmissions!
however, the same part number is used for all transmissions for 1st and 2nd
gears.  5th is unique to the later transmissions.  confused yet??

ok, so what gives?  if this is true, then the later 016 transmissions must
have had the same ratios as the earlier transmissions.  you could, on the
basis of this, make the case that the 1st and 2nd ratios did not change *at
all* between any transmissions because the 1st and 2nd gears on the output
shaft never changed.  also that 3rd and 4th ratios changed post nov '83,
only to change back again for the later a-series transmissions (asx, auk,
avc) but not the earlier torsen ones (apx and auh).  it is possible that the
earlier input shaft (mentioned in the fiche, but not in ekta) carried
different 1st and 2nd gears, but the ratio can't have changed because the
gears on the output shaft didn't change.

in summary, it looks as though the only gears which changed were 3rd and 4th
between 1st september 1983 and the 31st july 1987 (what i call the series 2
(of 4) quattro with the sloping grill), but then changed back again for the
mb and rr era transmissions (torsen).  anyone out there have any other ideas
or information?  and no the differential ratios didn't change.

the other relatively strange thing is the plethora of mb-era transmissions.
there is the apx and auh which started the mb era (1st august 1987), a year
later the asx and auk transmissions debut, with the asx continuing through
to end-of-life(!), while the auk lasted only 1 year (to the end of the mb
era).  with the 20v (rr) era commencing 1st august 1989, the avc
transmission debuts, and this continues through to end-of-life. so we have
four(!) mb-era transmissions, one of which continues through the 20v era,
and one 20v transmission.  why???  i would hypothesise that this was to
cover the swiss cars (the wx series) which continued through to the end of
the mb-era.  if this is true, it means that the "wx" series got the torsen
transmission.  it still doesn't explain the asx transmission though, or the
requirement for the auk (now there's a name).  any ideas?

thats enough for now, my head hurts....

dave
'95 rs2
'90 ur-q