What's the diff?

[QSHIPQ@aol.com]

>Well, I've done some pretty spectacular things in mine over the last 80000 
>miles, and have _never_ been 'bitten'.  I _regularly_ drift it sideways round
a 
>number of familiar traffic islands and, traffic permitting, I push _really_ 
>hard on the 70-mile twisty trip up to the Hickling meeting every month.  I've
>never seen a sign of unacceptable behaviour.

Maybe, our beloved El Nino could lob some snow across the pond to those
traffic islands Phil.  I have no doubt that you haven't seen it.  Many
haven't.  Doesn't mean it's not there.  Many have seen the dark side,
including some UK club members, per your own reports.

>It's not sufficient to say that Audi don't use a TORSEN centre differential 
>when racing.  Sure - they don't - but they don't use any other kind, either. 
>If I were to find a viscous coupled differential in a motorsport Audi, I
might 
>think they have a case to answer.

Not exactly.  I think if you take a look at the audi racing efforts thru the
80's you will find reports that show that audi used either the 50/50 split
locked Gen I in the early efforts.  Then in the later '80's fixed f/r biased
locked between 55/45 and 70/30 based on venue.  Only very recently your no
center diff racing came about.  Audi also used active, which is similar to the
f/r locked with a small adj for each corner.  Dave L indicated that some more
detail of active diffs can be found in the latest Racecar Engineering.  Volvo
was collecting data per track per conditions for programming active for a
specific track, then feeding into the computer program of that track.  I
hardly think Audi wasn't doing the same thing.  You will find the same
"deviant" intent to program behavior in F1 as well in regards to active diffs.
This follows exactly what happened with ABS in Indy cars.  Start programming
tracks, officials don't look kindly.

Scott Justusson
'87 5ktqwRS2
'86 5ktqw
'84 Urq