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Mike V wrote:
>Would be interesting to find out for sure. Doesn't appear they are
>at all with the fwd A4. However, they may still be semi-secretive since the
>quattros are still *very* competitive down undah. (Gotta love Speedvision...)
Be careful on this Mike. The material I gleened the 3 VC setups on quattro
(that would be awd really, 'quattro' would indicate that it's the same as the
street quattros, not the case at all), also compares turn for turn (by King as
well, Audi Sport UK Engineer) the differences between the A4q and the A4fwd.
The "quattro" advantage wanes with it's weight penalty in a big way. Some
exerpts for you:
King - "Off the start line the Quattro was phenomenal. Our entry and mid
corner speed was ofter better, with higher lateral g-forces in spite of the
weight (penalty). Mid to exit speed should have been better but the weight
penalty slowed the acceleration of the car. You would think that mid to exit
would have been superb - the car was more controllable but it was slightly
slower because the fwd car had its weight advantage."
"At Donnington you had the best of the quattros with Frank Biela driving and
the fwd a4s with Yvan Muller driving and they ran nose to tail for much of the
race. Uup to about 2/3 of the race distance the cars were well matched, then
the fwd car fell back as its tyres deteriorated."
>I do think this season clearly illustrates the "unfair advantage" of quattro
>when one compares results in the various TC series around the world.
I might agree except that the range of torque split on the quattros raced was
very narrow. In fact, 40/60 and 45/55 f/r VC splits were the only two used in
the A4s center diffs, and all used the same front and rear VC diffs, with the
occasional spool rear with the 40/60 setup. That would indicate to me that a
fwd A4 and a t*rsen equipped A4q would be a wash at just about any other
venue. Why? Well King, Biela, and Bintcliffe all point out the difficulty
in running any torque splits beyond this range. The unfair advantage, it
appears, is a stacked deck to the rest of us. No VC's were ever offered to
the rest of us, so a conditional "quattro advantage" can be claimed at best
with what is offered to the rest of us, 78/22 to 22/78 f/r. A reread of
King's comments regarding the 35/65 VC setup not really being used - too much
oversteer (not to mention that 78f certainly can be 'too much understeer' -
and what does that say about the 78r t*rsen torque split?), shows that the
quattro advantage would be hard proven for the rest of us on the street.
I'm fascinated by what King, Biela and Bintcliffe gave away in these articles.
I think the cat is very much out of the bag, down under so noted. Those
street A4 drivers that saved the 1500USD quattro option, certainly can stand
proud that the "quattro advantage" as defined in ST, is hardly a trump on the
street, or the track.
Since Audi is committed to fwd racing the A4, it should be interesting to see
a) what tire developments happen, and b) whether the traditional north-south
motor orientation changes. The competition in fwd, it seems, is the Honda
Accord (blasphemy!!), it has the E/W fwd advantage, due to it's lower and
reward engine orientation. The thought of the competition being an Accord is
revolting... I personally liked the M3 vs A4q idea better.
Stay tuned, and don't count those A4 fwd cars out yet. They are so close in
lap times to the A4q's (with the A4q's having the advantage of 'quattro'
specific tyres), that some tweeking could regain Audis reign in ST. King
seems to know exactly what the comparison is between the two (data logged
even), so the "quattro" advantage, could just help make a better A4 all-
Just my .02