Running Gear - Front SuspensionThis page will be developed with more in depth information, photographs, parts lists, torque settings and other stuff (like upgrades and repair info) as time permits. For now it will be a bit rough and ready.
The front suspension on ALL S2 variants is identical bar some anomolies over time that Audi swapped between forged and pressed wishbones. The front hub is bolted to the suspension strut such that they can be independently serviced in some situations which saves a lot of time and hassle. The 3B engined Coupes have slightly higher ride height than the ABY Coupes which were also a little more stiffly sprung than the 3B. Dampers on the Coupe are valved a little differently than the Saloon and Avant - to be confirmed... Another thing to note about the front suspension and the springs in particular is that cars fitted with air conditioning in the factory have stiffer front springs. That proves just how heavy the A/C components are ! The correct colour codings for the various springs will be added here soon.
Wishbones (aka Lower Transverse Links) The introcuction of pressed steel links was supposedly for cost saving measures at first but the forged parts were reintroduced through the S2 production... All very confusing, but I think the list below is an accurate indication of what was fitted in the factory. MY91 - 'H' chassis - FORGED Please don't take the above as gospel truth but it is a fairly good guide. I suspect the pressed wishbones were dug out for the MY95 cars as Audi had depleted stocks of the more expensive forged item. So why is this important I hear you ask? Well it's because the forged and pressed front wishbones take different sized bushes which is well worth knowing when shopping for these items and they are non-interchangeable. Each wishbones has two bush mountings where it attaches to the subframe. The bush for the front forged wishbone is
893 407 181 A hefty balljoint with a diameter of 19mm is attached to the end of the wishbone (where it takes the load of the front corner via the hub carrier) with nyloc nuts onto three captive bolts. These joints are sided and quite pricey from Audi so shop around when the time comes. Left lower balljoint is
895 407 365A. Right lower balljoint is
895 407 366A. PLEASE NOTE - When fitting new wishbone bushes it is not advisable to fully tighten them into place until the weight of the car is on the ground. Otherwise the bushes can take up an incorrect position which could lead to premature stresses and failure. Easy to say, but harder to do without access to a pit or ramp. It can be done with wheels on the ground with patience though.
Hubs & Bearings The front wheel hubs on the S2 have a diameter of 82mm as was the norm for all 80 series vehicles with an output in excess of 110kW. The S2 hubs have 38 teeth that engage with the correct driveshaft. The S2 hubs are unique to the 80 series in that they have a 5-bolt wheel pattern at a pitch centre diameter (PCD) of 112mm. This means that 5-bolt wheels from a VW or Porsche do NOT fit the S2. A whopping M16 bolt secures the hub into the driveshaft. The design for this bolt was changed at some point as the replacement bearing kit (893 498 625E) has a 17mm internal hex headed bolt in deference to the 26mm external bolt fitted in the factory. Also bizarre is that the front wheel bearing is common with one from the A4 (4D0 407 625E). This bearing is actually manufactured by none other than SKF with their part number ( BAH-0011 D) clearly visible. This should save a few quid. It is recommended that the hub bolt is replaced along with the bearing - available separately as 4A0 407 643. SPECIAL NOTE - The vehicle must be standing in its wheels when attempting to loosen or tighten the hub nut due to the high torque required.
Top Mountings The sheer weight of the S2 puts a great load onto these rubberised mounts which are sandwiched between the strut top and the bodywork. These are a common cause of knocking noises at the front when they fail, but driving pleasure may well be impacted before you notice the noises. Replacement part number is 8A0 412 323D , but the best upgrade in terms of value for money and sweeter handling is to use the tougher mounts that were fitted to the UR quattro ( 857 412 323D). These are a very similar price to S2 items, but are visibly different by their distinct blue colour. The top mounts fitted to the S2 and RS2 (and the V6 quattros of this genre) are green in colour.
Anti-Roll Bar & Link Rods The S2 has a stiffer (larger diameter) anti-roll bar (ARB) than other 80 models to reduce body roll. The front ARB is bolted to the chassis via two 'U' shaped brackets with split rubber bushes ( 811 411 327B) and a double jointed link rod which attaches it to each strut. These link rods take a helluva pounding so its not unusual for them to cause nasty noises at the front when the joints wear out. The design of these link rods was changed from a narrow metal rod to a much wider (and lighter) plastic part. Don't be surprised if you find the link rod nuts to be seized solid on older cars because an awful lot of water and grime makes its way around them and the inevitable fight ensues. Many S2 owners comment that they would like even less body roll for flatter cornering and handling. Such a feat can be achieved by fitting the even larger ARB (and its bigger bushes) from the front of the RS2. As always with bolt on suspension fixes of this nature, there is a down side - namely increased understeer. There are moves afoot to counteract that with a very much stiffer rear ARB to neutralise the S2 handling trait or perhaps even dial in some potential oversteer which some might like and others might loathe. Watch this space ! PLEASE NOTE - When refitting the ARB it is not advisable to fully tighten it until the weight of the car is on the ground. Otherwise the bushes can take up an incorrect position which could lead to premature stresses.
Torque Settings (from OFRM via Erwin)
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Last Updated 17th April 2003