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ST250 2014
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Current situation:

Bluefin, Quaife diff, Eibach springs (down by 25/30), ITG CAIS. I am happy with the power output and looking to increase adhesion on bends even more. The car sticks to the road pretty well now but wonder if front and rear anti-roll bars would be beneficial. Any opinions?
 

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Nick - Mk3.5 FL ST3 Moondust Silver
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I don't know about the Mk3 yet but putting an uprated rear ARB on my old Mk2 helped a lot by making it turn in a lot easier & reducing the understeer. I haven't noticed the same need on my Mk3 yet but admittedly it is not running as much power as my old 500 - yet!!
 

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:thumbsup: If you fit both front and rear uprated ARBs on a front wheel drive car they will cancel each other out so although the car feels like its cornering flatter you will not go any quicker and are more likely to lose grip. Fitting just the uprated rear ARB will give more grip to the front wheels though. We can supply the Hardrace uprated rear ARB for £175 or if you did want both for £360.

Front ARB

Gesture Font Gadget Electric blue Audio equipment


Rear ARB

Circuit component Audio equipment Font Rectangle Electric blue
 

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:thumbsup: If you fit both front and rear uprated ARBs on a front wheel drive car they will cancel each other out so although the car feels like its cornering flatter you will not go any quicker and are more likely to lose grip. Fitting just the uprated rear ARB will give more grip to the front wheels though. We can supply the Hardrace uprated rear ARB for £175 or if you did want both for £360.

Front ARB

attachicon.gif
201510221115211V15E2WE copy.jpg

Rear ARB

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201582514202214T20S22IN copy.jpg
How easy is the rear ARB to fit ? Is it a DIY job for non mechanic people ?
 

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Nick - Mk3.5 FL ST3 Moondust Silver
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:thumbsup: Its very easy to fit as long as the bolts come undone ok. If the bolts or droplinks are very rusty though it can be a pain to get undone.
Rusty bolts & bits on a Ford - never!!!!!

I would just assume that it is a four Haynes spanner job & get the oxy-acetylene kit, crowbar, lump hammer, & 9" angle grinder ready. Then douse them in penetrating oil 24 hours prior. If they all then come off with a spanner put the extra kit away & then go & buy yourself a lottery ticket!!

p.s. Mine didn't quite need the oxy-acetylene but they didn't come off with just a spanner!!!
 

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:thumbsup: If you fit both front and rear uprated ARBs on a front wheel drive car they will cancel each other out so although the car feels like its cornering flatter you will not go any quicker and are more likely to lose grip. Fitting just the uprated rear ARB will give more grip to the front wheels though. We can supply the Hardrace uprated rear ARB for £175 or if you did want both for £360.

Front ARB

attachicon.gif
201510221115211V15E2WE copy.jpg

Rear ARB

attachicon.gif
201582514202214T20S22IN copy.jpg
I am looking to upgrade these and have been looking at your products. I was wondering if you could explain to me a little more about why the fitting of the Front & Rear would effectively make the car handle worse?

Thanks!
 

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Graham - mk2 stage 3
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I was wondering if you could explain to me a little more about why the fitting of the Front & Rear would effectively make the car handle worse?

Thanks!
You need to understand what an anti-roll bar actually does. It will reduce the slip angle. So a rear one will let the rear slip earlier thus improving the turn in for the front that has stock slip angle.

Hard suspension will reduce roll but the tyres will loose grip easier. Soft suspension will give more roll but the tyres will have more grip and the cornering forces work on the body first then the tyres.

The legendary (at the tine) Lotus Elan had very soft supension but IIRC firmer shock absorbers and it cornered on rails. It was also very light so the cornering forces were lower.

Fitting a front anti roll bar decreases the front slip angle = understeer.

Many years ago I had an Austin Healey Sprite (RWD) that was tail happy so a front anti roll bar evened it up so the handling was improved by reducing the front grip a bit. Then I could dial in from understeer to oversteer by around a 2psi difference in the front and rear tyres.
 

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I'd like to dispell a statement.

Fitting both front and rear anti roll bars don't cancel each other out, they just keep the chassis balance close to standard. The roll is still reduced so provided your tyres have enough grip it increases the threshold of cornering speed and the weight shift also needs more speed to happen.

It's more a track thing really. If you uprate only the rear bar and use the car on track, at those speeds you'll end up with a rear biased car that feels tail happy and not have the confidence in it to push harder to the tyre limits, especially on a tighter track that makes it weight shift more.

Big disclaimer though, it does make the car ride choppy due to the diagonal stiffnes being increased.

When I fitted the MK3 rear end in my MK2 it became out of balance again. I used to run a 25mm rear bar and 24mm front bar which worked fantastic with the Quaife. The MK3 has a 22mm rear bar so it became a little understeery again. I swapped the front back to stock and it feels nice again. Got rid of some choppiness. Haven't driven it on my test road yet. Still needs the tracking done.

I could have uprated the rear MK3 bar but I was looking for more comfort. I'll possibly uprate the shocks later instead and leave the rest alone. The car feels awesome, turns in so well with the MK3 front end giving extra caster.
 

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Both very good explanations. I was definitely not understanding the primary function of an ARB and also not applying logical maths/science to the idea.

Knowledge gained!

What do you mean exactly when you refer to "choppy"?
 

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Well an anti roll bar is basically a torsion spring between both suspension arms and attached to the subframe. If both wheels move together it just pivots up and down in the chassis mounts and does nothing. If one wheel moves the other side resists the movement effectively holding that side down and tyres on the road but if you go fast enough it will lift the inside wheel putting more pressure on the outside wheel. Even if both move, if there is uneven movement it still resists. It puts a diagonal stress on the chassis and the extra spring action of it loads the shocks more, making them less able to control the movement. It's firmer and makes wheel movements sharp and choppy. If the balance is wrong between both ends the harder end kind of kicks back into the other end. Doesn't feel good.....
 
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