You can never have too many RS4's...

[Don@STaSIS]

Thanks go to another local RS4 onwer in the Bay Area for giving us the opportunity to install our Motor Sport suspension on their car. Again an absolutely beautiful car... No matter who sees the car or where it is, on a lift, in the shop or out in the lot, people gravitate towards it. Lots of thumbs up, curious people from nearby shops and track employees had to come a second time to find out what that noise was. On a more technical note we rated the stock springs since this RS4 was still running stock equipment on arrival at the shop. As suspected, soft for a car of this girth. RS4 B7 OE Suspension Front Springs - 400lbs, linear Rear Springs - 410lbs, linear (measured at spring) STaSIS Motor Sport Suspension Front Springs (Street) - 750lbs, linear Rear Springs (Street) - 1200lbs, linear (measured at spring) We are nearly doubling the front rate and are tripling the rear. Note that rear springs can be measured at the spring, as we do for our kits, or at the wheel which will yield a lower number since this is an inboard spring design. This also means that Audi is running a lower spring rate at the wheel in the rear than in the front which does not help eliminate understeer, it actually promotes it as a handling characteristic. As folks running our Motor Sport suspension on their RS4, S4 and A4's can comment, even with this jump in spring rate the comfort is maintained while providing a much flatter ride. The RS4 can take more spring as well for the aggressive street/track enthusiast without compromise. Again a great vehicle with so many amazing characteristics. I'd love to start seeing some of the more track oriented customers come out of the wood works to run some higher spring rates, would truly make a tough package to beat on the track! Cheers!

[BenM@University Audi]

Shouldn't be that hard, should it?

[Parikh1234]

if you are installing it for free, id ship my car out to the bay area

[Don@STaSIS]

[wizo2g1]

I might make the jump after all.

[2000s4biturbo::Uli]

[James P.]

Stasis has been disabling the DRC I believe when performing the upgrade.

[Don@STaSIS]

[abwc]

Are your figures comparing OE rear spring rates to Stasis rear spring rates comparable ?

That is, are both the rates quoted obtained by measuring at the spring in both cases, or is one rated at the wheel and the other rated at the spring ?

Intuitively, it seems to me (a suspension layman) that, since the rear of the car is lighter, you would need less spring back there.

And, even if the rear OE setup was biased toward understeer, why would it take 300% more spring to make the car neutral ?

[Don@STaSIS]

a real function. With our Motor Sport suspension we always maintain a higher rear spring rate to help neutralize the understeer that is created by the weight distribution and forward placement of the engine in front of the axles. For comfort only a lower rear spring rate will work well, however due to the Ohlins dampers we use we can run a higher rear spring rate than that of the front while maintaining the comfort level. This affords the benefit of neutralizing some of the understeer this chassis exhibits. We run even higher rated spring rates in our A4 B7 WCTC race cars with a larger split between front and rear. For street use we prefer an approximate 100lbs at the wheel difference between front and rear spring rates, favoring the rear.

Now without the proper damper that is valved correctly this could yield a terrible ride. You are correct that there is less weight over the rear and for comfort alone with a lesser damper a lesser rear rate would be optimal, just for comfort however. Since our Ohlins dampers are designed to work with this level of spring and the rear is specifically valved for these spring rates we can maintain the road going manners of the car while helping balance the chassis to eliminate some of the understeer. In no means does this 100lbs split make the car twitchy or an oversteering monster on or off throttle, however as one owner here has described, he can now power out of a corner since having our Motor Sport setup installed.

For a very track oriented setup you might find us running a 900lbs front with a 1500lbs rear, possibly more in the rear. This car would exhibit a far more neutral behavoir, however for street use we would want not want the car to be on the edge of neutrality into having a twitchy oversteer oriented behavoir. This is not ideal for safe street use, however on a track or open course it would flatten the RS4 even further than our standard rates and help to make the car far more balanced for an experienced driver.

The nose weight of these cars and placement of the motor relative the front axle makes for some nasty understeer which the Quattro drivetrain can only make up so much for. Balancing this with spring rates is an effective method and due to the Ohlins dampers is a viable option when comfort is still required.

We've run these splits on this chassis for years now and it definitely helps, even if it does seems excessive. The split can be higher and the rates higher as well if you truly want to balance the chassis. It truly is amazing to think that we are tripling stock rates while maintaining a comfort level near stock with a firmer and flatter ride. The Ohlins damper is that advanced, it can handle this change which is definitely to the benefit of the handling but allow the streetability to be maintained 100%.

Cheers,