ARB upgrade: Rear only or both?

[P_G]

Just curious as to hear fromTTRS and RS3 owners or suspension gurus that have done an ARB upgrade and what they have gone for. On my S4 I upgraded the rear one only to the B7 RS4 one and it made a great difference to the car. On my RS4 I changed both to Hotchkis and still maintain it was the best value modification I made to the car.

This time round I have the choice of H&R's kit for both front and rear or 034Motorsport's rear bar only. There is an obvious price difference between the two kits but set that aside H&R is 24mm front (adjustable) and 22mm rear (fixed) and the 034 is 22.25mm rear and adjustable. I'm tempted by the latter TBH but as it is from the US I suspect not many have gone this way and most reviews will be H&R. I just feel that if I went H&R to get the best out of them it would also need springs, haldex controller etc.

Thoughts appreciated.

[RIV]

If the rs3 rides anything like my sport back I would say the springs are a must to replace, I'm doing this soon, I reckon springs first then see what the car handles like, then arbs.??

[P_G]

The springs are pretty good and bearable, no more harsh than the RS4 DRC on 19's but the turn in; whilst there is grip there eventually it does understeer and rolls and it's this I want to eliminate if possible. Complete coilovers is a step too far for me with a 7 week old car and my R&D budget!

[P_G]

Do I take it from 75 views that no other RS3 owners are considering doing this to their car?

[hammy969]

Sorry PG
Can't help you on this one. I have limited knowledge when it comes to suspension set ups.
I do understand what you are trying to achieve though and I will be interested in the outcome.

[RIV]

So I take it the rs3 doesn't have a choppy almost bouncy ride when going over uneven roads at speed?

[SteveCuz]

Trouble is none of us have done it yet so it's impossible to comment. I upgraded the ARBs on the RS6 along with coilovers and it transformed it but can't comment on what your suggestions will do to the RS3 and which will be better.

Steve

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Without any specifics to the car... standard logic that I've used would say that if you have understeer and roll then the rear arb would be the best bet.
If you update both then you'll have less roll, less overall grip, more steering response and the understeer... well pretty much unchanged.
The roll doesn't cause the understeer so it more balance that you are after - so with the rear arb you're reducing the grip slightly to balance the understeer on the front.

However the haldex (I think the rs3 has one) throws a curve ball in this for me as quite frankly I've no idea how this reacts to things mid corner.

[dbm]

Do I take it from 75 views that no other RS3 owners are considering doing this to their car?

I am considering it, but haven't taken the plunge yet.

I had an 8L S3 which I did extensive modification to (including updated ARBs at front and rear plus coilovers). It transformed the car - that and the updated brakes had more of an impact on the real-world performance than chip and cooling did.

I've come to the RS3 from a TTS which was fantastically level, and so the body roll on the RS3 is a little off-putting to me in the corners. That is what I was primarily looking to improve on, though talk of just updating the rear is interesting as I haven't heard of the pros for this before. I would speak with one of the established tuning companies and ask their advice - I've used Awesome-GTi in the past and their engineers know their stuff.

[dbm]

So I take it the rs3 doesn't have a choppy almost bouncy ride when going over uneven roads at speed?

No, the RS3 is much better damped than the S3 as I understand it.

[P_G]

My concern with the H&R is that it is trying to increase grip with flatter cornering all round to minimise understeer rather than dealing with balance issues. The rear bar upgrade only, has worked for me in the past on the S4 although admitedly it had a heavy V8 engine up front and torsen. That said on the rolling road the Haldex IV gave nearly 50/50 power distribution between front and rear axles whilst on there so it appears a decent system. If I went rear bar only and need more grip on the back afterward to stop the rear feeling light I could perhaps go 235s all round rather than 235/225 front/rear at present.

Here's 034's blurb (BTW from what research I have done on the Audi US forums 034 have a good reputation over the pond);

034Motorsport is proud to offer the ultimate rear sway bar upgrade for the Audi TTRS & Audi RS3! The 034Motorsport Adjustable Solid Rear Sway Bar is made from high-quality spring steel for maximum rigidity, and is designed to combat understeer while reducing body roll under hard cornering.

This product was tested thoroughly on the street and track on the 034Motorsport Audi TT RS 2.5 TFSI before release. The 034Motorsport Adjustable Solid Rear Sway Bar substantially reduces understeer and body roll on the Audi TT RS & Audi RS3 without compromising comfort on the street.

In addition, the 034Motorsport TTRS Rear Sway Bar is engineered to be used effectively with the stock front sway bar. No upgrade in the front is needed or required. The addition of a stiffer front bar introduces even more push, requiring an even bigger bar in the back. With the stock front sway bar and upgraded 034Motorsport Solid Rear Sway Bar, body roll is virtually eliminated while turn in and off throttle oversteer are greatly improved.

The sway bar rate is adjustable via the adjustment holes. The two holes closest to the MOI of the bar are the "stiff" (423% stiffer than stock) setting, and the two holes farther out are the "soft" (362% stiffer than stock) setting.

Features:

Adjustable - 362% or 423% Increased Sway Bar Rate vs. Stock TT RS Rear Sway Bar
22.25mm Diameter
Solid Spring Steel Construction
2-Hole Adjustable
Easy to Lubricate Sway Bar Bushings - Zerk Fittings Included
Designed to be used in conjunction with the stock front sway bar.
What's Included:

034Motorsport Audi TT RS & Audi RS3 Adjustable Solid Rear Sway Bar
Graphite-Impregnated Urethane Bushings
High-Strength Sway Bar Brackets with Lubrication Ports
Sway Bar Retaining Clips


I see the TTRS lot change camber settings first at the sacrifice of tyre longevity then ARB's.

[geek]

So I take it the rs3 doesn't have a choppy almost bouncy ride when going over uneven roads at speed?

No it doesn't; the suspension feels well developed albeit capped and compromised - dialling out the understeer completely would probably induce to rigid a setup and make it difficult to live with.

I have zero chasis complaints other than understeer and tyre feedback.

The grip up until the limit is impressive, I would forgive it much more if the tyres gave decent feedback rather than just grinding and vibrating, understeer doesn't have to be such an unpleasant experience! Twisty roads don't induce on limit behaviour when using throttle and brakes when you should, roundabouts and fast s switch backs do though; stay off the power until the apex or the point at which you can pin and not lift and it just grips and goes - even with s@ite tyres. To be clear, the car still corners admirably even when understeer is induced, it just complains its arse off whilst it does it making it not much fun; with progressive capable rubber I am convinced the situation would improve dramatically.

PG, I like the look of the adjustability of the 034 ARB; love the comment about not setting it to maximum stiffness in the set-up instructions - sounds like a challenge more than a warning

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So I take it the rs3 doesn't have a choppy almost bouncy ride when going over uneven roads at speed?

No it doesn't; the suspension feels well developed albeit capped and compromised - dialling out the understeer completely would probably induce to rigid a setup and make it difficult to live with.

Depends what you're doing though and where the understeer manifests itself.
Generally the softer you make something the more grip available at that end.
It's why a lot of hot hatches go "tripod" when being pushed as the rear arb is so hard trying to fight the natural tendancy for fwd to understeer.

The key is to work out and isolate when and where the understeer is happening - corner entry, mid stead state, or exit.
if it's turn in then you could fit a harder arb and soften the front damping to compensate - you could be aiming to retain front end grip whilst controlling body roll and then upgrade the rear arb. Shouldn't drastically affect ride...

But to be honest, if you don't want to compromise ride then you really need lots of cash on a 3/4 way adjustable shock and set the fast and slow bump/rebound appropriately.

[geek]

Oh how I would love the budget to be able to not worry about warranty and to fettle to create the right set up.

I am struggling to get past the apparent limitations of the tyres, they provide such little feedback and break traction in such an unpleasant way I think it is difficult to judge the quality of the standard chasis set up. The majority of the driving so far has been in luke warm / cold, damp wintry conditions. Getting the car onto a decent benchmark footing of warmish dry weather and decent tyres has to be the starting point for me.

To be clear and fair, the Conti's are perfectly adequate up until the break point, the lateral grip when nailing all but the tightest of corners is excellent - my skill and bravery fades before the tyres do in standard point to point conditions and I am brave! (no skill claimed )

Its a toss up I think between PSS's and F1's. I have thousands of miles worth of experience on PS2's on M's so will probably go the Michelin PSS route unless an F1 user can convince me otherwise - given that you can get a full set of four for the RS3 for the same price as a set of rears for an e61M5 I think it is the most logical place to start.

Will be following PG's efforts on the ARB front with interest.

Just had a realisation that I am more interested in chasis mods with the RS3 than I am with power.....must be getting old

Sorry PG, just realised I am rambling away in your thread

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Chuckle
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