Snow Driving

[Peter Berrevoets]

OK so here goes...

My problem with the torsen (which I rather like) and the stock setup is that
it allows one front and one rear to slip big time, something I discovered
when ice racing with some fo the s-car guys last year. The problem was
really bad when drag racing and really annoying when trying to cut corners
on the hairpins that made up both ends of the course.

The really poor traction just spun two wheels and the all-wheel drive
benefit wasn't.

Seeing as the 90-94? V8 had a torsen equipped rear diff and the 944 also
uses a limited slip torsen in the 016 it has rear mounted, what would the
downside be to using those components in say... my 200TQ giving it torsen
front, mid and rear?

That to me would seem to be an ideal performance solution, using reasonably
modified street power with an MC2-10V or perhaps an AAN-20V, for road,
gravel, snow and ice use. Not wanting to get into the racing aspects of its
(the torsens) power handling limitations it has me thinking and I'm keeping
my eyes open for the right bits to appear at one of the local wreckers.

Any thoughts?

Cheers!

Peter

Cheers!!

Peter

1990 200Q MC2
1989 200Q MC1 Parts
1987.5 Coupe GT NF
AAN on shelf...

> -----Original Message-----
> From: quattro-admin at audifans.com [mailto:quattro-admin at audifans.com]On
> Behalf Of QSHIPQ at aol.com
> Sent: Thursday, December 05, 2002 10:38 AM
> To: scott at dreamtheater.zzn.com; quattro at audifans.com
> Cc: torsen at audifans.com
> Subject: Snow Driving
>
>
> Ok, I'll chime in here.  For any specifics of lockers, please
> read my yearly
> Steamboat reports.  Scott, specific to your post, comments inserted.
>
> In a message dated 12/4/02 2:47:41 PM Central Standard Time,
> quattro-request at audifans.com writes:
>
>
> >having driven both types of quattros (non torsen and torsen), I must
> >say that I do enjoy the torsen type of the 200q, despite not having
> >the ability to lock the rear diff at over 15 mph.
>
> Try interrupting the blue white wire that goes to the controller under the
> seat.  The 15mph lockout can be modified.
>
> >On my 5ktq, I could spin the tires in rain before the center diff
> >would control it, either that or the speed. I would go through front
> >tires pretty quickly, nearly the same as my 5kt 5speed.
>
> Unlocked I presume?  Since locked this wouldn't hold true.  That must be
> either one heck of a 1.8 bar mod, or crappy tires.
>
> > BTW- I run
> >1.8 bar. Also, the 5ktq would't track straight on hard, wet launches
> >or over wet painted roadway stripes. I'd have to lock the center,
> >losing abs. I have locked up all fours doing this, too. Was able to
> >kick the rear of the car out regularly :)
>
> A locker without ABS isn't such a bad thing.  As Bob pointed out, ABS only
> gives you the ability to steer impending lockup.  A locked center diff
> however, gives you ideal brake force distribution, which, if you
> know how to
> threshold brake, can be infinitely better in terms of braking
> than ABS.  In
> the scenario above, the torsen and the locked diff would behave
> identically.
>
> >On my 200, I feel this system is superior. Very hard to kick the rear
> >out. More balanced tire wear. Car lauches straight, all the time.
>
> Actually, the rear comes out easier on a torsen car than on a
> locker or open
> diff car, it's the nature of the device.  Turning radius makes the torque
> shift rear on a torsen car.
>
> >Can't really spin a tire.
>
> That's because Trg goes down when you do.  Some consider this a
> good thing. I
> don't
>
> >Next, even without locking the rear diff,
> >its pretty tough to spin a tire.
>
> The torsen works the same with or without locking the rear diff.
>
> >I enjoy how automatic the system is;
> >I retain the abs in bad conditions.
>
> Well, the system isn't "automatice" it's a LSD device.   It's passive.
>
> >On highways, panic manouvers, I
> >have more control under power, evidenced by my 85 mph swerve around a
> >wrecked police car on I 80 in Pennsylavnia this past Sunday.
>
> You *don't* have more control under power, you have less, by
> definition.  The
> torsen hunts during any turn, since it can't accomodate slip.  Which means
> that as you were swerving under power (I won't comment on the
> circumstance),
> the torque allocation was shifting, it appeared to work for you this time.
> Counting on that could prove disappointing.
>
> >I like
> >that I can just relax and drive. IMO, this system feels like it's
> >doing more than the type that preceeded it.
>
> It is doing more, the debate is whether that's a good thing or not.
>
> >I like that hard 1.8 bar
> >launches don't produce wheelspin, just forward motion in a straight
> >line.
>
> If you are doing a hard launch, you could lock the diff, in a
> straight line,
> there is no difference in torque allocation between a locker and a torsen.
> I'm intrigued by the definition of a "hard launch",  I have 2 10vt lockers
> running 22psi, my comment:  That's one *hard* launch.
>
> >On power turns are great because the car goes where it's
> >pointed at high boost levels.
>
> It can't by definition.  As you turn a torsen car, torque
> allocation goes to
> the rear, if that torque allocation rear, causes the rear tires to lose
> traction, torque allocation goes to the front 56% of it.  IME,
> that isn't the
> definition of "going where it's pointed", it just can't without some other
> sort of corrective action.
>
> >I managed the spin my 5ktq around oing
> >the same thing.
>
> Drivers school?
>
> >To avoid a war, this is based on my driving habits only. I like the
> >torsen equipped cars.
>
> I'd only suggest you understand what the device is capable of,
> and what it's
> not.  Right now, you are assuming a lot of things that the device, by
> definition, isn't capable of.  Which means that someday, based on your
> driving habits, the device is going to let you down.
>
> >Next, it's a bad idea to use simultaneous braking and throttle on a
> >torsen vehicle because the power will be distributed to the axle with
> >the most braking.
>
> Scott, if you look at any of the offroad sites, you can see
> contradiction to
> this statement abounds.  In fact, the MOST effective way to
> control a torsen
> is to apply braking while on throttle.  This reduces the torque
> shift antics,
> especially in high torque/cf ratio environments.  I wouldn't at all agree
> with the above statement, in fact, the exact opposite is true.  Power is
> distributed to the slower rotating driveshaft, period.  ANYTHING
> that causes
> that to be true will recieve the most torque.
>
> I'm not with you on this post Scott.  The torsen cars *can* illicit good
> behavior when properly used and understood.  That said, a properly used
> locker in low cf environments would be difficult to best with a torsen AND
> abs.  Any winter driving school (high torque/low cf ratio) will reinforce
> that.
>
> HTH
>
> Scott "torsenboy" Justusson
> lockers aplenty
> 87 type 44tqw 22psi lockers
> '84 RS2URQ project lockers
> '83 Urq electro pneumatic locker conversion
> '86 type 44tq lockers
> '87 4runner turbo lockers
>
>
>