diff interchangeability, Quaife/A4/4kq/540i?

[auditude at neta.com]

On 12 Jan 2002, at 2:17, Brett Dikeman wrote:

> At 10:16 PM -0700 1/11/02, auditude at neta.com wrote:
> >Hey all,
> >
> >Check this out.  It looks like the Quaife part number for the rear A4
> >quattro diff is the same as the front 4kq part number.  As a matter
> >of the fact, the same part number is listed for a BMW 540i
> >
> >http://www.quaifeamerica.com/differentials/diff_apps.htm
>
> No...one begins 30, the other begins 40...the rest of the part
> numbers are the same, but the first two numbers aren't.

Oh yeah, I see that now.  Must've been up too late in front of the pc
or something.  It looks like only the Bimmer diff is different (hehe,
"diff"erent).

Are their any differences or advantages between the front 4kq diff,
and the A4 rear diff?  Is the A4 diff a Haldex or anything?  That's
what I'm wondering.  Also, is the Quaife diff for the 4kq the one that
controls the open front two wheels, or are we talking about the
"center" diff between front and rear?  I would think if it's the same
part as the rear diff of an A4, that it would be the front diff between
the front wheels on tehe 4kq, since it is changing direction 90
degrees.

I'm just wondering if a stock A4 rear diff has any advantage in the
front of a 4kq, for example if an A4 owner has put a Quaife in
his/her car and had the stock one for sale.

> I would, however, be interested to hear where these diffs will work
> on other cars.  A rear quaife diff would allow for a more V8q-like
> setup on the 200q20v, for example.  Actually, I wonder if the rear
> differential assembly from a V8q could be put on a 200q20v...nah,
> probably not.  The other question is...would it be worth
> it...probably not, is my guess...

I'm not familiar with the V8q differences from the 200q20v.

Ken