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Re: Differential Locking vs Driving style

In a message dated 96-02-08 12:16:33 EST, you write:

>I think my success with the rear-only diff lock for auto-x is due to my
>driving style and past vehicle experience and is not related to the tires. I
>switched from yoks to a used set of BFGs for the 94/95 season, due to one of
>the yoks getting trashed when my ex-spares car was moved. (Hi Chris! Jab Jab
>:) I had the same success with the rear-only diff locked setup with the BFGs
>and with the yoks.
>I come from a big-block V8 waaaayyyyyy overpowered-type race vehicle (RA IV
>455HO CP '73 Firebird) and enjoy a tail-out steer-with-the-throttle driving
>style. The rear-only diff lock setup gives the 4KQ more of a
>rear-wheel-drive handling style and all but dials-out the dreaded understeer
>(along with appropriate tire pressure differential F&R & properly tuned
>Konis). If you are coming from a FWD or heavy understeering or
>underpowered-type vehicle (honda, etc) and/or use more of a finesse driving
>style then the the all-open setup may very well work best. I like a
>toss-it-into-the-corner and steer-with-the-throttle driving style, more
>Pro-Rally like and certainly not a finesse style, but, hey, it works for me.
>I did find that the hot setup with the ur-Q was with both diffs locked, but
>we're talking almost double the HP of the 4KQ in this case.
>Try experimenting, but then stick with what works for *you*.

........  Coming from a prorally background, as well as road racing, can
share this:  If you NEED to lock the diffs on a 4kq or a urq on a dry track,
some serious looking at the chassis might be in order.  Specifically, SPRING
height, Spring weight,roll angle, ackermann effect, Chassis dynamics, and
driving style....  I assure you, glen, High HP does not lend itself to your
proposed style, BTDT....  If you are driving that way and getting BETTER
times, you have a CHASSIS problem, look hard at where and why.....  If you
don't want to correct it, you are correct in your assessment.  However,
putting/making up with/for design compromises should not be a goal, but a
target for improvement....

A properly suspended quattro, should not LIFT it's inside wheel, which is the
only reason you need to lock the rear diff......   Tossing a q into a corner
properly without the rear diff locked, will still give you throttle on
oversteer (at hi hp), as well as lift throttle oversteer.  The stock setup on
the q's is initial understeer, and lift throttle oversteer.....  Both Eric F.
and I use the open diffs on all tracks to date, and dragging a 100% rear
locked diff around the track is proven nowhere in racing, especially on a
road course......   No offense intended to Glen or Steve, if it works for you
go for it.....   Is it THE method for gaining speed, not in engineering or
practice.....  Look hard at that suspension, make the changes to make the
chassis right, then forget locking the diffs till Steamboat arrives next FEB,
or maybe in the rain at a road course....  I might encourage a look at the
center lock if you have traction prollums, but since my car is in the 350+++
mark with none, again I would encourage proper setup vs locks, I have yet to
spin a tire on a dry trackwhile on line, so the why question comes to

A driving course with proper instruction, properly executed racing lines are
not rocket science, they are there, regardless of vehicle, what awd does to
that line is only on the exit of a turn on full throttle.....  If you are
doing it any differently, a couple of rides with Eric might be in order......