RS2 anti roll bars

[Greg_S]

I didnt realise until i read the write up on the RS2 the other day that it had different anti roll bars fitted.

has anyone fitted these? do they make a great deal of difference to the handling?

and if so whats the damage and will they fit the coupe S2?

[s2driver]

I did this change about 6 months ago.

After spending some time on the Russian EKTA site (I can speak and read a bit of Russian) comparing Audi 80, S2 and RS2 suspension parts it turned out all I needed to do was buy a pair of bushes and a replacement roll bar for each axle. The brackets that mount the bushes to the subframe are identical between RS2 and S2. If you do some basic torsion calculations it works out that the RS2 roll bars are twice as stiff as the S2 at the front and about 6.5 times stiffer at the back. If I remember right, the front goes up in diameter by 2 or 4 mm and the rear by about 6 mm (data not to hand sorry). In reality this is not quite right becuase the ends of the roll bar is experiencing some bending moment and I could not be bothered [img]images/graemlins/shocked.gif[/img] to try and get it modelled dynamically in analytical software.

I cannot describe the transformation: it 'feels' totally different. In terms of predictable handling things didn't really change that much i.e still a piece of cake to modulate the car between oversteer, neutral and oversteer just on throttle and steering mid corners. The body roll was reduced significantly. Though this probably doesn't really contsitute more true grip on the road it does make you and passengers think that it handles much better. It probably induces slightly more oversteer if anything. It is not going to make you any faster round the corners unless body roll un-nerves you at the moment, or you are a non-progresive steerer. One situation that it will really improve things on a standard sprung car is during the infamous mouse-avoidance test (the Scandanavian magazine test that cost Mercedes a fortune when the original A-class was rolled onto its roof). The test involves swerving to avoid an 'obstacle' that 'steps' into the road in front of you. Bigger anti-roll bars would tend to transfer much less momentum-to-body-roll during a sudden flick of the steering. So, in this case, handling made safer.
No comfort changes noticed.

The difference is going to be a lot more noticable on the standard suspension. As standard the car is very softly sprung for a bit of comfort for the labrador in the boot of the avant, can't comment on Coupe but it must be similar except the dog has to be smaller [img]images/graemlins/crazy.gif[/img]. If you have already gone for uprated shocks and springs all around the stiffness contribution of the roll bar (across-car load transfer) is going to be much less noticable.

It is probably a bit of a placebo but I prefer the handling with the RS2 roll bars just because it stays much flatter in the bends and NOT because I get any more grip. A good mod for about £250 (parts only from Audi direct). I even fitted them myself at home in the dark on the driveway ( [img]images/graemlins/mad.gif[/img]because my worklight broke just after I started [img]images/graemlins/mad.gif[/img]). It still only took an hour; better facilities would probably turn that into 30 minutes tops.

I haven't got the part numbers to hand but I could dig them out for you if you are interested. BTW I have an S2 Avant so "Fit a coupe?" Front: yes highly likely....rear: not sure without another half hour on EKTA (crap internet connection at home).

If your car has done high mileage and it has been thrashed around the twisty stuff (like mine) then I would recommend changing the S2 roll bar bushes anyway (and wishbones', but that's another story). They have to work so hard because of the softness of the standard suspension that mine had noticable physical wear to the bush AND the bar. So why not replace the whole lot anyway.

IMHO tyres are the most critical selection to improving S2 handling performance. Predictability of handling was too shocking on some big name brands but So-2's best I've tried so far: a statement also repeated throughout Porsche, Saab, 205GTi etc. forums. I have just fitted some 235/40YR18 Goodyear Eagle GS-D3 but haven't run them in yet to really test the grip out. Yes they fit but it is bloody tight when you go from 7.8 to 9.5 inch section width (www.tirerack.com for manufacturers data) and I have just had to buy some 3 mm thick spacers due do some [img]images/graemlins/shocked.gif[/img] Rizla [img]images/graemlins/shocked.gif[/img] clearances.

Sorry for the waffle but basically:

1.Good mod: makes car flatter in corners and less 'wallowy' during emergency maneouvers;
2. £250ish parts only;
3. Not sure if it fits the coupe at the rear unless I do some research on EKTA.

Lee

[Doug_RS2]

Brilliant - Could you please have a quick look at the Coupe - to see if you think it would fit. Sounds worthwhile - You didn't happen to try the car with the changed rear and standard front anti roll bars - just wondering if it was less understeery. These proices are from Audi UK? Did you get a quote from www.vagparts.com(import parts for Audi Germany) - wondering if it's even cheaper.

I've changed the wishbone bushes on an S2 before - Have you got any comments/ insights to changing yours? I',m going to be doing it on my current one soon. I was going ot go with Koni/H&R springs/ poly bushes all round and the blue top strut mounts - but might try the roll bars and not go for such a harsh spring/shock combo.

Dougal

[Greg_S]

looks like the roll bars will be a worth investment. the reason i ask if they will fit the coupe was because of the discussion on brakes recently with the differing type on the avant to the coupe.

as for mileage on mine its only on just over 80k so will leave bushes till i do roll bars or they need doing because they are awakard to do arent they.

brake discs are the next priority after i get some new wheels. hopefully should be getting some 17's with continental contisports. dont know if you have used those before?

[s2driver]

I will have a trawl tomorrow whilst at work.

Fitting rear only: I wouldn't. Understeer cured by decent tyres on mine not by making chasis lose grip on unloaded inside rear tyre whilst cornering. Just stiffening the rear will probably give you major oversteer! Before changing my tyres there were some roundabouts..er..I mean short radius corners on a racetrack that I could only take at 40mph before the onset of understeer and possibility of whacking a kurb before exiting. Decent tyres but before RS2 ARB change, same corners over 60 mph with absolutely no understeer. I've even gone in at 80, braked well too late and still held it together coming out the other side: so predictable and forgiving, although I did have to use up a lot of road (and plenty of opposite lock)!!

Price: UK Audi (Martins Basingstoke because they are tops for service IMHO). Couldn't try vagparts at the time as I don't think it existed and www.partsdepartment.co.uk had some issues: can't be more detailed on that subject.

My comment about the wishbone bushes is that mine need changing, desperately. Just ordered a polyurethane set for the front this morning from Demon Tweaks (probably not the cheapest but I was buying a load of other stuff from there anyway). If I get them in time I will fit them this weekend.

Not thinking about suspension too much at the mo as my brakes are completely shagged. Upgrade within the month and then I can start looking into suspension seriously! I use my car every day so I am prioritising maintenance. She's done 130k miles to date so there a few worn parts that need replacing. I only bought new wheels to fit a decent brake setup and I am only doing this because my pads are getting thin. Well, OK, wanted something that wouldn't fade within 30 seconds of commencing a kamikaze mission.

Some UK tuners claim cracked bodywork on polyurethane equipped cars but I am not convinved with the S2 until I see it! There is another series of bushes between the subframes and the chassis which should still provide some NVH/shock isolation.

I will post a picture as soon as I get one taken in daylight and you will see that I can't go for the Koni setup unless I can retain standard springs. My new (oversize) wheels have completely filled the arches and lowering 30 mm will result in major problems as it will be another 30 mm 'less available' travel before hitting bodywork.
The standard shocks are now tired after a gruelling life. Squats under acceleration and dives under breaking don't do your chasis dynamics much good: standard springs with uprated/adjustable shocks for me please!

Other option could be from the German firm KW-Gewinderfahrwerk (translated to KW-adjustable systension!). Variant 2 is a full spring-platform-adjustable coilover set with damping adjustment whilst variant 3 offers this plus rebound adjusment. If I decide to go for the variant 2 kit I will buy it next time I drive to Germany it is only around £800 (1200euro). I would fit myself and then get it properly aligned as I did with my previous car. These kits are great quality and fully TUV approved. Loads of German tuners use them but not much coverage over here [img]images/graemlins/frown.gif[/img].

Give me about 3 months and everything should be sorted. Just decided to cancel a holiday to NZ to pay for much needed maintenance and tuning goodies. Sad? Maybe? Don't car! Puts a grin on my face!

Lee

[s2driver]

as for mileage on mine its only on just over 80k so will leave bushes till i do roll bars or they need doing because they are awakard to do arent they.

I've done bush changes before. Hardest bit is getting the old bush out (and making sure you don't screw your camber when re-fitting the wishbone. I recently changed an outer front CV boot and taken the whole front end off to change some ancillary belts: now that's what I call awkward!

Roll bar change is a piece of cake: two bolts per bracket, one bolt per strut connection. Front sumpguard has to come off but thats only a couple of quarter turn fasteners. I didn't even jack up the car: just drove in onto a line of concrete blocks lying flat on the ground, 4" extra height enough to do the job easily.

Lee

PS shouldn't be hard to research the coupe to avant differences: might just take a little bit of time.

[Andiroo]

Nice to see a bit of creative engineering that results in positive change. It's all too often we hear about the same suspension mods on springs and dampers, that just stiffen the suspension, with no qualification as to whether it is better - excellant reports Lee [img]images/graemlins/wink.gif[/img]

Andiroo

[Bushy]

I agree

Great content Lee top man

[johneroberts]

I agree too , well done Lee on a excelent post [img]images/graemlins/nodder.gif[/img]

[s2driver]

Cheers guys.

Right, had a long look through all of the different models and I can confirm that you can definately stick the RS2 ARB on the front of the Coupe by buying 2 RS2 front bushes (8AO 411 327) and one RS2 front ARB (8AO 411 309).

Can't do this for the rear though I am afraid. Different setup entirely . S2 avant and RS2 are extremly close to each other but the coupe is dissimilar.

If someone has a set of ramps they can take my standard rear ARB and compare it to the one on a coupe. If it is of any use I can bring it to one of the meets.

It sounds sad but I would be interested to know anyway so wouldn't mind having a look myself.

Lee

[Doug_RS2]

Bu99er - I can't think what the rear anti-roll bar looks like and it's too cold outside - It isn't the same as the front by any chance - on the coupe!

I got a set of Powerflex bushes from Demon Twats. It took 8 weeks to get the correct parts - ended up getting powerflex to send them direct and they sorted out Demon for me. Check before you take out the old ones that you have the correct ones.

I don't buy the poly bushes shagging the car - I think people are getting mixed up with poly bushes and nylon bushes - The poly bushes replace the original rubber bushes that have the metal inner liner and outer liner - The poly bush does not have the outer liner - more material to flex - I reckon they probably move nearly as much as new rubber ones but are a lot more consistant over time. Am I making sense here?

[Greg_S]

from posts and articles ive read in the past i believe the coupe is the same front and back. not certain on this. so the remedy may be to use the thicker standard S2 ARB from the front on the rear and fit an RS2 version up front or for even stiffer rear ARB use the RS2 front on it.

the reason i say this is because the bush setup is the same front and back isnt it?

will have to have a look next time mine is on the ramp in a couple of weekends time

[s2driver]

Can't confirm or deny. Tell me if you are making it to a meet soon and I will bring both of my standard ARBs and someone is more than welcome to take them for comparisons to the Coupe's.

I believe that the subframes are different front and back but it is plausable that the ARB bush-to-chasis is common on the Coupe front and rear. It isn't on the avant however.

[Greg_S]

i checked the ARB's a while back while i had mine up on the ramp. But i dont think it would be feasible to use a front on the back anway because the difference in diameter is huge anyway.

So if you did do the change it would almost certainly alter the handling to barely controllable.

Demon tweeks are doing one from whiteline for the S2 but there is confusion as to which model it will fit, coupe, avant or sedan.

Greg

[90quattrocoupe]

Hi,
Hope you don't mind a yank chiming in on this rear sway bar issue for coupes. Here in the states, one of the options for rear sway bar is to use the front lower suspension arms from a 4000K quattro, replace the rear arms on the coupe, and then you can use the 26mm off the front of that car.

The arms bolt right up to replace the rear lower arms on the coupe.

Should be big enough for your needs.