GlesgaKiss

Hi all, is there any chance someone could explain to me what the various effects of different anti-roll bars are. I notice alot of the members on here have all the whiteline gear etc. How much difference does it all make?

Cheers, Alan

cusco kid

hi m8 roll bars alter roll stiffness .they can make or brake a cars handling ,with the correct set up you will transform your gird .they can alter understeer, oversteer, ect .loads of charistics are altered by arbs geo

corradoboy

When you turn into a corner the centrifugal weight transfer of the vehicle is called roll. As the weight to the rear of the car rolls the car onto the loaded sides suspension, a roll bar is twisted in opposing torsion from the loaded to the unloaded side. The thicker the ARB the more resistant it will be to this and the less the car will roll. The most adverse effect of rear end roll is bizarrely to the front of the car, as the front wheels are pivoted off of their ideal alignment, reducing the tire tread contact patch and thus reducing grip. With a stiffer bar and less roll, the front tires stay in better contact with the road surface, increasing grip and making higher cornering speeds achievable. On the downside, the stiffer it all gets the twitchier it becomes as the roll is the tell-tale sign of what is happening through the corner. When a car doesn't roll and more forces are applied through the tire tread during faster cornering, when the limits of that tires adhesion is reached it may break loose suddenly. Very stiff ARB's are better if you are a smooth and progressive driver, but the Whiteline 22mm is fine for most offering a marked improvement over the OE 19mm item, especially when used with more rigid drop-links than the flexible OE plastic items.

GlesgaKiss

Thanks, both replies have been alot of help and cheers corradoboy for going into that depth.

Alan

dunx

iTrader: (3)

Hi Alan,
As I'm bored waiting for some bits to come....

A rear bar helps the car corner flatter, helping front end grip, so reducing understeer. On fully stiff this made the car a bit "drift-spec"....

When I later added a front bar the front end grip was increased further, causing the rear to be less of a problem, (24 mm rear on full stiffness).
This set-up is a bit "crashy" over harsh ridges, but mine's more toy than daily driver.
The ALK feels best over heavily cambered roundabouts, where before fitting I couldn't use full throttle as the front end lost grip as the nose of the car lifted. Now sorted I feel 340 bhp is easily tamed, and have started to chase more....
HTH
DunxC
P.S. I like mine on it's standard set-up for now, but if I need an up-grade there is the option of coil-overs....

bob r

iTrader: (46)

You won't like this but I think I am in a minority with my opinion..............when I changed my oe bars to 22mm front and rear with uprated rear droplinks I don't think it made the car handle any better. Maybe it's because I have never really pushed the car in the handling dept before or after the mods?

corradoboy

A waste of money then.

GlesgaKiss

Yeah I was considering starting with a 22mm rear bar as I dont want to go too far with it just yet. Mine is a toy as well, as I dont need a car to commute . Thanks for replies, helpfull and interesting learing more about this stuff.

Alan

GlesgaKiss

Also, how simple is all this stuff to fit? I was thinking very! lol but I havnt had a go at it yet. Surely its just a case of remove old and bolt on new?

Cheers, Alan

dunx

iTrader: (3)

Rear end is an hours work including coffee.... make sure you get drop-links as the original bolts on my old dog snapped as I tried to remove them. I didn't even jack the car up, easier if you don't.

ALK and front bar need some muscle and a bit of gear, my "locals" (PreciousMetal) did it in an hour, they had free fitting as a deal a while back.

HTH

DunxC

911

Agree with you all!

Adding these mods will take something away from road/daily driver comfort and ease of control that Subaru spent millions on to get right for Joe Public globally.

The fact is these mods really do make a difference, but there is a 'price' to pay.
Unless you drive an Impreza enthusiastically, then these mods are pointless.
If it really is a weekend toy, then get stuck-in.

In my limited experience of weekend road/racing (serious racing, not just trackday blasts with a mate):

Stock is very limited, very safe, very comfortable.
Add 22mm rear bar soft/middle hole adjustment and steel/alloy drop links = a nice move forward in the bends, un-noticeable on the high street.

Move bar to max stiffness and things warm up, better in the bends, jiggles appear...

Add a 22mm bar to the front and rear and a bit better in the bends, car roll reduced noticably, + a few jiggles on the rough high street.

22mm front/24 rear.
Chassis gets very nice (IMHO), especially with rear bar set on middle hole.

IMHO, you need more to balance things. Minimum ALK and a very good alignment job + nice tyres. Great weekend/daily driver if you are enthusiastic.

From this point you need to add a lot more, but a good mod with the 22/24 would be Sti suspension or Eibach springs on good stock dampers.

The difference the rear stiffness setting makes is not to be underestimated.
Some understeer will be dialed-out which makes for far better control and much faster/safer cornering.
You do have to be prepared to experiment, and some will like it this way, some another. It has to be right for you as the driver, so all this is general rule stuff!

To remove understeer in the dry needs a lot more changing, but an Impreza without understeer is a dream come true!

Mods, mods, mods:



It works:
22/24 rear + minor mods years ago:
DropShots.com
Full-house mods 2 years ago:
DropShots.com
Lat year with the interesting Whiteline 27mm front/24 hard bars and roll center mods etc, really nice in the dry! Class win/record too!!
DropShots.com


Hope this chat helps.

GlesgaKiss

Thanks dunx, part of the reason for making the change is droplinks need replacing soon anyway. Will start with the back anyway, n see how it feels. Will let you know how it went.

Alan

GlesgaKiss

Yep, very helpfull and interesting to read, good vids.

Its a toy but not on the same level as yours. lol

My goal is to just basically get it perfect for the summer, Its nice spending time on it.

Cheers, Alan

bob r

iTrader: (46)

Perhaps not. If I were to find myself going round a bend a little quicker than I would have really wanted to, then the uprated ARB's should prove their worth.
Otherwise , I may start to push the car a little more when the dryer weather comes.

dunx

iTrader: (3)

LOL bob r !

Mine keeps doing that to me ! 'Cos it doesn't understeer anywhere near as much as it used to. I'm heading for a geometry set-up soonest.

But seriously, in this crap weather I tend to take it easy.
But once you push the car harder it will feel better, honest.

DunxC

bonzee

iTrader: (2)

we'll going on the advice of 911 and dunx when i was after arb front and rear
i must say it was the best money i've ever spent,my car goes around bends like its on rails 200% better.
22mm front 24mm rear both adjustable well worth it

good fun to..... hard rear,soft front.

911

Bonzee likes oversteer!
Good fun chassis' aren't they!?

bonzee

iTrader: (2)

brings back my mk2 escort days just not as much sideways

bren@apex

iTrader: (20)

91,

I hope you dont mind but I have a few questions. Im trying to get our Impreza to its optimum whilst not going overboard with the engine and drivetrain. I dont want to be doing anything further powerwise.

What would you recommend roll bar wise for a car used mainly on track but that also needs to retain a decent level of drivability for road use thats running 6/5kg.mm spring rates?

22/24mm?

What roll centre mods did you do? On our 200s and Skyline we run anti bump steer rod ends and taller ball joints, do you do a similar thing with the Imprezas?

What springs do you run out of interest, and what sort of drop from standard ride height?

Bump steer rod ends

Ive got a set of these for an Impreza but our car isnt particularly low so I dont feel the need as yet.

Tall ball joints

We have also installed these, they come complete with bearing type joint rather than rubber and are all adjustable so pretty cool

Alignment arms

Although I couldnt feel a lot of drivetrain and engine movement whilst driving it was clear just when reving the engine at stand still from under the bonnet that the standard mounst arent the stiffest so we installed a set of these.

Engine and gearbox mounts

dunx

iTrader: (3)

Over to you 911 !

bren@apex

iTrader: (20)

You might like these, theyre the next step up from just taller ball joints and are what we are installing on both of our competition S13s, our S14a and our Skyline for 2008

Adjustable lower front arm

Adjustable lower rear arm