Rear anti roll bar worth fitting?

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joeseth
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Mon Jun 24, 2013 8:42 pm

Just remembered my car doesn't have a rear anti roll bar! Is it worth fitting and can you feel a big difference? Also If I fit one will it be worth going for the thicker touring one? And also my car is quite low, does the arb foul on anything or does it just help e.g. Rear wheel not rubbing on hard cornering?
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zaust
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Mon Jun 24, 2013 8:56 pm

To be honest it depends on your springs and shocks. yes it will help on cornering if you have a softish set up, how ever it will help the back step out if the set up is stiff. I release mine on track day's.
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magpie
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Mon Jun 24, 2013 9:25 pm

i have one from a 318is with all the drop links ,brackets and bolts ready to bolt straight on .

drop me a pm if interested .
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DmcL
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Mon Jun 24, 2013 9:26 pm

interesting to know.. so no rear ARB seems to work better on track days with non standard (lowered spring/aftermarket shocks)?

also how much thicker is the touring rear ARB and are the 4 pot and 6 pot touring rear ARB's the same thickness? touring rear ARB might be a nice little sneaky upgrade for my 325i at some point without going aftermarket.
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Mon Jun 24, 2013 9:38 pm

DmcL wrote:interesting to know.. so no rear ARB seems to work better on track days with non standard (lowered spring/aftermarket shocks)?
More ARB on the rear means the rear trailing arms have less independent movement, which means the rear wheels, which deliver the drive have less traction, as they can't conform to the profile of the track as easily.

The stiffer the suspension, the less need for an ARB, as the body can't roll as much. The problem with super stiff suspension is it gets to a point where car reacts too much to the bumps in the road/track, making the car uncontrollable.
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Mon Jun 24, 2013 9:43 pm

DmcL wrote:also how much thicker is the touring rear ARB and are the 4 pot and 6 pot touring rear ARB's the same thickness? touring rear ARB might be a nice little sneaky upgrade for my 325i at some point without going aftermarket.
http://www.e30zone.net/e30zonewiki/inde ... i-Roll_Bar
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joeseth
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Mon Jun 24, 2013 10:08 pm

Hmmm seems like there isn't a definite answer to this one. Well to set the picture my car isn't mega hard on the rear springs, not like it is on the front any way. And like I said the rear wheel can rub on hard cornering. It's my daily and I don't track it, but I do like it to handle well. Only have an open diff aswell so sideways action is to a minimum at the moment haha. Non of this info probably helps :?
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billgatese30
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Mon Jun 24, 2013 10:34 pm

An anti roll bar will reduce the independence of the suspension across an axle. I.e the compression of the outside will be resisted by the inside trying to lift (I could just say lift a front wheel when cornering on track due to my ARB/Spring setup). In the wet I use to disconnect the rear ARB as I wanted to regain as much independence as possible, but there will have been more 'body roll' due to it.

If you are on super low springs, with an open diff, then putting the power down out of tight corners may be a bit more challenging if you are driving quite hard. If you are experiencing rubbing at slower/normal speeds then you may benefit from a rear ARB, but you would probably also benefit from rolling the arches.

If I was you, get a second hand ARB and try it, if you don't like how it handles, then sell it for what you paid. If you like it, then everyone is a winner, only you will know if you like how it handles with one fitted.

A little more basic reading here
http://en.wikipedia.org/wiki/Sway_bar

More in depth reading here
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joeseth
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Tue Jun 25, 2013 8:10 am

Cheers, very good advise! Think the wheel rubbing I will have to live with because of my choice of wheel (16x8 et0). Mite be able to get the arches a little flatter.
'89 Lachsilver m42 coupe - Sold
'92 Laguna Green Convertible M50
'97 e36 328i sport - Daily
'89 Alfa Romeo Sprint cloverleaf
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