Star Performance Testing Day – Pt8 Anti-Roll Bars

Ess_Three

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The factual bit:

As many of you know, I spent many hours down at Star Performance two days ago…12 hours in fact (08:45-20:45) having a play, testing a few things, having a load of work done, trying out a few things etc.

Firstly, thanks to Jim & Brian…12 hours and two meals later we were all knackered!
Credit where it’s due…anyone looking for decent service, advice and standard of work could do a lot worse than giving them a shout.

Secondly, none of this was free…labour rates, wheel alignment rates, dyno time, replacement parts…all paid for out of my pocket...I have the invoice for over £900 to prove it!!

Thirdly, these are our (mine, Jim’s and Brian’s) observations based upon our findings. All testing carried out with conditions kept as close to previous conditions as possible etc…some will disagree violently, some will agree…that’s your prerogative.

Now we're getting into the juicy stuff...ARBs!!


A bit of background info:

S3 anti roll bars are as follows:
19mm Front, 15mm Rear (mine are anyway)
Not a bad balance...still understeers...but managable - just!

Out of interest, early TTs - you know the ones, the ones that actually handled but people complained they used to pop the back out if you lifted off in a bend at 130 MPH - had the following: 19mm Front, 15mm Rear
Same as my S3.

Late TTs -after the factory had ******** up the handling - have the following sized ARBs: 20mm Front, 14mm Rear

Now anyone who knows how ARBs affect a cars set up will confirm that normally, the larger the front bar, the more the understeer. And, the smaller the rear bar, the more the understeer. Late TTs have a larger front (more understeer) and a smaller rear (even more understeer)...which may explain why they feel so bad to drive (they do to me anyway!)
...anyway, I digress.

Back to ARBs...
To me, what I want to do is limit the roll of the chassis without going too extreme on the spring / damper rates...as explaines in Pt7 I now have the Bilstein dampers and H&R springs, neither of which are overly stiff.
So, fitting larger bars F & R will limit roll...the dampers are still fit to control them...but the car still understeers...what to do?
Well, the answer is to fit a larger front and rear bar, but to ensure the rear bar is proportionally larger than the front.

I trawled through ETKA and found a 21mm F ARB available off an early A3 1.8Tq...but no proportionally larger rear bar...but what's this in the Neuspeed catalogue?

22mm Front, 19mm Rear
Hmm...3mm thicker on the front and 4mm thicker on the rear.

Now, if my memory regarding ARB twinting forces serves me well, a 2mm thicker bar = twich as stiff as the original...4mm = 4 times stiffer and 6mm = 8 times thicker...I think that's correct (square rule and all that!)

So a Neuspeed 22mm front bar is somewhere around 3 times stiffer and the rear 19mm bar 4 times stiffer.
...the problem being that the ARBs are listed for a TT.

Neuspeed also offer a 25mm front ARB...what's that all about! Understeer city!
Forget that...that'll make it understeer even more...I'll stick to the 22mm bar.

I gambled (not so much of a gamble really...ETKA shows all the clamps, bolts etc to be the same between TT & S3)...and with much help from the kind chaps at Awesome GTI Store, I obtaind the Neuspeed 22mm / 19mm combination.


So, they are on:
Rear...not too bad a job: drop the exhaust, heat shields etc, disconnect the ARB drop links, change the bar, bolt it all up.

Front...nightmare! Power steering rack off the subframe, balljoints off, ARB drop links dissconnected front subframe completely removed from the car, change the ARB...and get it all back together...not an easy or quick job.

But they are on...and combined with the dampers, the handling is a revelation!

Less body roll, and best of all...it turns in like a proper drivers car should, crisp, predictable...the front grips well with no noticable understeer at any detectable speed (not tried it in the wet yet). I like it.

More details on chassis tweeks to follow in Pt9!!




 
[ QUOTE ]
Less body roll, and best of all...it turns in like a proper drivers car should, crisp, predictable...the front grips well with no noticable understeer at any detectable speed (not tried it in the wet yet). I like it.

[/ QUOTE ]

Oh no that sounds like another recommendation too me!!!

I dont think ill be able to bring myself to read part 9.

Do you know with all this testing that your going to 1. upset my bank manager and 2. REALLY upset my girlfriend as i promised i wouldnt 'do' anything to my S3

and now i have a list thats now getting bigger and bigger /ubbthreads/images/graemlins/mad.gif

Great job though Ess Three /ubbthreads/images/graemlins/beerchug.gif

Thanks

Mark

p.s. do you think just upgrading the rear ARB by a mm or two will have a similar effect as i dont like the sound of all the work involved with the front?? Is a 17mm rear even avialable??
 
[ QUOTE ]
AL B said:
This is what the forum has needed for a long time.

Well done.

AL

[/ QUOTE ]

Very much so!

Rich
 
Glen,
We've never met and to the best of my knowledge or hers (that she's admitting to anyway) you've not met her either. However, she doesn't like you at all. I think she mentioned something about you ruining our holiday to Thailand. /ubbthreads/images/graemlins/laugh_roll.gif
Top work fella. Totally test-tastic!
GBH
 
the S3 ball joints are a different part number than the A3 so they may not fit into your hubs, I dont know if the arms will fit to the subframe though.
 
Finally, I understand ARB. Def think the 4motion rear bar upgrade sounds worth it. Understeer is cronick!

Quality post.
 
the standard r32 roll bar is 19mm, which will be a lot cheaper than the neuspeed one.

i had thought about fitting the 20mm front with the 19mm back - difficult to say whether the 20mm or 21mm front from the a3q would be better with the 19mm rear.

 
Rich,
Took a look on the HDD last night, and no luck /ubbthreads/images/graemlins/frown.gif I didn't take any pics of my ARB swap. Prolly cause it was DARK when my dumbass did it /ubbthreads/images/graemlins/crazy.gif /ubbthreads/images/graemlins/grin.gif

/ubbthreads/images/graemlins/beerchug.gif
 
[ QUOTE ]
Wee Marky said:
Hi Guys!!

How does these tweaks effect the ABS and EPC

Thanks

Mark

[/ QUOTE ]

ABS unaffected...it's stand alone...although loads of negative camber will tend tobring the point at which it operates in a straight line down a bit.
Big Brembo's don't help that either!

EPC?

In my experience, the point at which the onset of ESP is detected is actually improved. The car rolls less so the ESP detects less pitch and roll and hence is less likely to come into play and spoil the fun.

If you get it sidewards the lateral G is still there and the Yaw will still be present, so the safety function will still perform as designed...but so far it seems less likely to step in and prevent unwanted activation.
 
On shocks and dampers, I have H&K Coilovers that only gave me about 25mm of drop from standard on my S3 with 17s and they are excellent.

Dan
 
To revive an old thread, would the 23mm front and 19mm rear ARB's from the R32 actually bring MORE understeer to my TQ?? I have to replace the suspension anyway, (looking at H&R Springs with Bilstein B8's) and thought this would be a good time to replace some bushes and maybe even the ARB's. Thing is.... I can't afford the Neuspeed set (Can barely afford the R32 set) MAINLY cause I've ordered the Forge adjustable tie rods for the rear /ubbthreads/images/graemlins/cool.gif
I've already gotten the 16mm rear from the 4-Motion Golf on, and it helped a little, but think that going for just the 19mm R32 rear would be too much.

Any thoughts?(Glen?) /ubbthreads/images/graemlins/confused.gif

Thanks /ubbthreads/images/graemlins/beerchug.gif
 
[ QUOTE ]
Drill said:
To revive an old thread, would the 23mm front and 19mm rear ARB's from the R32 actually bring MORE understeer to my TQ??


[/ QUOTE ]


Remind me Drill...what's the standard TQ ARB sizes?
You could probably go either 21mm or 23mm front with a 19mm rear...you should try and keep the rear bar proportionally larger than the front, so I'd neen your standard sizes to best advise.


[ QUOTE ]

I have to replace the suspension anyway, (looking at H&R Springs with Bilstein B8's) and thought this would be a good time to replace some bushes and maybe even the ARB's.


[/ QUOTE ]

You'll not be disapointed with that set up...


[ QUOTE ]

Thing is.... I can't afford the Neuspeed set (Can barely afford the R32 set) MAINLY cause I've ordered the Forge adjustable tie rods for the rear /ubbthreads/images/graemlins/cool.gif


[/ QUOTE ]

At least you have the tie bars...you'll struggle to get predictable handling without them.


[ QUOTE ]

I've already gotten the 16mm rear from the 4-Motion Golf on, and it helped a little, but think that going for just the 19mm R32 rear would be too much.

Any thoughts?(Glen?) /ubbthreads/images/graemlins/confused.gif


[/ QUOTE ]

Just the 19mm rear on standard dampers would be a no-no in my book.
Since you are adding the H&R / Bilstein set up, you may be OK...again, I'd need your front and rear ARB sizes to say...

Are you still running the S3 17" wheels, Drill?

After many months of driving between myself and David R, switching between the original 17" wheels and the 8" x 182s I had on...we concluded that the set up I had was great for 18" wheels, but not so great for 17" wheels - it understeers more as the tyre moves around on the rim (taller sidewall).

This being the case...and assuming you have no plans to go up to 18" wheels...you may be better going down to a 21mm front ARB, rather than going for the 23mm of the R32.
The R32 runs 18" wheels don't forget...and it would always tend to understeer if pushed hard in the wet - hence me choosing a 22mm front rather than a 23mm R32 front.

Looking back, it appears that some TQs had the 21mm front bar - has yours?

Let me have your standard ARB sizes...


I'm tempted to say that I would be inclined to avoid the 23mm R32 front bar...
I think I would be tempted to go for a 21mm / 19mm set up and make sure you reduce the rear tyre pressures a little (I used to run mine well above standard pressure anyway...maybe you don't) to tame the rear end a little.

Tyre pressures make much more of a difference on the 17" wheels as you have more flex in the sidewalls to play with...I'm sure you could run 21/19 on 17" wheels, with bespoke tyre pressures and end up with a very agile set up without any risk of lift off oversteer etc...
 
My std ARB's were 19 / 15 although I've upped the rear to 16mm /ubbthreads/images/graemlins/crazy.gif You are correct in that I run 17's (In the Summer /ubbthreads/images/graemlins/angel.gif) although they're BBS VZ's (Would LOVE some Avus' for winter though /ubbthreads/images/graemlins/grin.gif). I also found running 36 psi all around to be best (based on the S3 suspension) so once this is done, I'll have to play around a bit. Did you drop just the rear, or lower the pressure up front too??

You said some TQ's had a 21mm front arb?? Any idea which? My ETKA only goes up to 2003, but all I could find on the 8L was a 19 or 20mm /ubbthreads/images/graemlins/confused.gif Where do you think I should look?

Thanks for all the help / advice /ubbthreads/images/graemlins/beerchug.gif
 
[ QUOTE ]
Drill said:
My std ARB's were 19 / 15 although I've upped the rear to 16mm /ubbthreads/images/graemlins/crazy.gif You are correct in that I run 17's (In the Summer /ubbthreads/images/graemlins/angel.gif) although they're BBS VZ's (Would LOVE some Avus' for winter though /ubbthreads/images/graemlins/grin.gif).


[/ QUOTE ]

Ok...and your standard stuff is 19/15.
Going to R32 23/19 isn't going to proportionally stiffen the rear then...
It'll corner flatter, but will still tend to understeer.


[ QUOTE ]

I also found running 36 psi all around to be best (based on the S3 suspension) so once this is done, I'll have to play around a bit. Did you drop just the rear, or lower the pressure up front too??


[/ QUOTE ]

I ran standard S3 front pressures, and upped the rears to nearer that for 4 passengers plug luggage.
That'll help the rear rotate...

36psi all round sounds a bit high...might be wrong...I can't find all my scraps of paper at the mo, they've got all my notes on them.


[ QUOTE ]

You said some TQ's had a 21mm front arb?? Any idea which? My ETKA only goes up to 2003, but all I could find on the 8L was a 19 or 20mm /ubbthreads/images/graemlins/confused.gif Where do you think I should look?

Thanks for all the help / advice /ubbthreads/images/graemlins/beerchug.gif

[/ QUOTE ]

It seems from my first post that it was from an early TQ...no idea what age though.
As for where you should look..Etka? /ubbthreads/images/graemlins/grin.gif
 
Damn dude /ubbthreads/images/graemlins/crazy.gif Talk about a blast from the past /ubbthreads/images/graemlins/grin.gif I think that was one of the first times I spoke with Gambba /ubbthreads/images/graemlins/lol.gif

Thanks /ubbthreads/images/graemlins/beerchug.gif
 
Hmm, couldn't find the same info on my ETKA /ubbthreads/images/graemlins/confused.gif Maybe it's a UK thing?? Anyway, I DID find the 20mm ARB. Do y'all (Glen??) Think a 20 / 19 mm setup would balance out?? Or would that be a tad too much in the rear, leading to oversteer???

Thanks again /ubbthreads/images/graemlins/beerchug.gif
 
20 / 19 might be great...
But there again, it might be dangerous. I can't say...I've never tried it.
I would say 21 or 22 would be safer...but, it's up to you...
 
/ubbthreads/images/graemlins/lol.gif Well THANKS /ubbthreads/images/graemlins/lol.gif

I guess I'll go in to Audi with that 21mm part number and see if it's available for the LHD /ubbthreads/images/graemlins/grin.gif

Anyone know of a 22mm ARB on the aftermarket??

Thanks again /ubbthreads/images/graemlins/beerchug.gif
 
OK, found out that the FWD A3's and Golf's had the 21mm ARB, but the Quattro / 4-Motion's only went up to 20mm /ubbthreads/images/graemlins/crazy.gif

Glen, based on your experience, what would you EXPECT from a 20 / 19 setup? Would it be too strong up front?

Also, I looked in ETKA and the part numbers are different for TT ARB's. Any idea if the Neuspeed 22mm front ARB for the TTQ would fit? Are there any major differences between the A3Q and TTQ setups?

Thanks /ubbthreads/images/graemlins/beerchug.gif
 
Whoops, I had it wrong.... the std ARB's for mine were 19 / 14 so the 16mm bar I have fitted is actually 2mm larger. Would this make any difference? Also, will be ordering the H&R Springs w/Bilstein B8 shocks tomorrow /ubbthreads/images/graemlins/grin.gif I'm also planning to have the bushes replaced (110k + miles on them) was gonna get poly ones for the front, and std rubber bushes for the rear, any advice/comments on that?

Oh, and once I get the Forge bars for the rear, what should I get the camber set at vs. std?? IIRC you said -0.5 to -1.0 but which do you think is better for std autobahn driving?

Thanks again /ubbthreads/images/graemlins/beerchug.gif
 
hi all so can anyone tell me what is the best set up for handleing and sreet use tar
 
As stated in the original post, 22mm front, 19mm rear but you can also fit R32 ARB's (23mm front, 19mm rear) which will retain the same factory balance but improve handling and work out much cheaper than aftermarket ARB's... don't fit with std dampers and springs though as it will affect the handling in the wrong way due to std items not being good enough to react to the extra stiffness afforded by the bigger ARB's

<tuffty/>
 
cheers tuffty so it will be r32 arb's then when im up for it also dampers and spring can i go for mate