Re: GF Test: Sports suspension for the A4

[Gary Bracken <gbracken@dimensional.com>]

Thanks, Tom.  Great information.  We appreciate your efforts!

Gary Bracken
Denver, CO

Tom Nas wrote:

> Hi all,
>
> As promised, this is a translation of the test in Gute Fahrt (German
> magazine concentrating on VW/Audi) 2/98 of several sports suspension setups
> for the Audi A4.
> I've somewhat condensed the article, and hope that everyone realises that
> neither German nor English is my native language- my 'on the fly'
> translation could be somewhat hard to read sometimes.
>
> ________
> In this test, four sports suspension kits and one spring kit are judged
> against Audi's original sports suspension. Gute Fahrt tests Bilstein,
> Eibach, H&R, Koni and Sachs. The test shows: lower doesn't equal harder.
>
> Handling test
> On a marked circuit, several quick and slow turns have been set up, and the
> lap times are measured for each setup. Two test drivers each rate turn-in
> response, steering precision and dynamics as well as braking and traction.
> Both this and the lap time are used for the final score.
>
> Slalom test
> The slalom test with the usual traffic cones setup with 18 metres in
> between was also timed. On top of that, roll and pitch were measured. These
> tests (as well as the avoidance manoeuvre test and comfort test) were
> conducted with both driver-only and car loaded to 80% of its capacity.
>
> Avoidance manoeuvre test
> Somewhat like the now (in)famous elk test, a quick lane-change manoeuvre
> without braking excecuted to rate high-speed stability was conducted
> several times with speeds being raised for every round until the car's rear
> end lost traction. In this GF test the speeds can go up to 100 km/h (60
> mph) and even over that. The maximum attainable speed of the car in loaded
> and unloaded conditions, as well as its handling 'on the limit' were rated.
>
> Comfort test
> A good sports suspension doesn't sacrifice too much in the way of comfort.
> This was tested on a series of road surfaces, driven at high and low
> speeds. Ground clearance was also rated. Like the safety-related items,
> comfort was also an important factor in our overall conclusion.
>
> Other tests
> The kits were also tested for ease of installation, fit and protection
> against corrosion.
>
> Comments
> Koni and Bilstein sets were somewhat harder to install because of the
> distance rings needed on the rear struts- those for the Bilsteins even
> needed some modifications. In the comfort test, the real surprise was the
> H&R-equipped car: a lowering of 50mm notwithstanding, the car remained
> quite comfortable. Even with a full load, comfort hardly suffered. The only
> caveat is that care is needed when driving up a steep ramp of some sorts.
> In the avoidance manoeuvre, the Audi setup as well as the Koni, H&R and
> Sachs kits did 100 km/h without a problem, whereas the Bilstein kit started
> to lose control at 95 km/h in a way which was hard to correct. Even less
> pleasant was the response of the spings-only Eibach kit. The combination
> with the regular (soft) dampers of the standard suspension turned out to be
> quite unpredictable. If you go for the Eibachs, the fitment of firmer
> struts is an absolute necessity.
> The handling tests showed clearly the two different objectives of the
> lowering kits and real sports suspension kits. The low and hard H&R setup
> excelled in the timed runs, but the carefully-weighted Sachs kit was only
> tenths of a second slower- in front of the Koni and Bilstein kits that
> overall equal the factory sports suspension.
>
>                 Audi OE    Bilstein  Eibach Springs     H&R     Koni    Sachs
> _____________________________________________________________________________
> Fitting            ++         +             +            ++       +       ++
> Quality             +         +             +             +       +        +
> Avoidance (empty)  ++         -             -             +       +       ++
> Avoidance (loaded)  +         O             O            ++       +        +
> Slalom (empty)      +        ++             O            ++       +       ++
> Slalom (loaded)     +         +             O            ++       +        +
> Handling            +         +             +            ++      ++        +
> Steering precision  +         +             O            ++       +        +
> Body roll/pitch     +        ++             O             +       +        +
> Comfort (empty)    ++         O            ++             O       +       ++
> Comfort (loaded)    +         +             O             O       +        +
> _____________________________________________________________________________
> Overall rating  very good  acceptable  acceptable   very good  good  very good
>
> Ratings:
> ++      very good
> +       good
> O       acceptable
> -       sufficient
> --      insufficient
>
> Hope this table comes out OK (use a monospaced font).
>
> There are detailed pros and contras of each kit in the article, which for
> anyone interested I'll try to translate. The accompanying graphs however
> are harder to convey via e-mail.
>
> Tom