Rear ARB decision.

right after playng around with my set up on paper and experiences from other coupes ive been in i know that a rear arb makes a world of difference.

i would love to buy the Eibach kit, but jsut cant afford it at this moment in time so my other option is to go for a whiteline rear arm..

looking at which one to go for..

they do a 22mm and a 24mm rear arb.

ive been told by a track lover that a 24mm will make the back end a bit lively...

but what will the 22mm do to the car?

the full spec to be fitted to my car shorty will be..
koni's + Eibach
camber bolts (-1 degree)
poly bushed front end (lower arms, drop links, front arb 23mm bush's)

i have been thinking about hub spacers but i dont want to put extra pressure on the hubs.

advice needed please!

Marco

22mm is a straight fit, the 24mm will need custom brackets making.

I have the 24mm on the back of mine (with D2 rear shocks and springs) and its the single best handling mod I have done.

my back end is really stable with the 22mm and i have heavier springs in the rear than the front.
you could add a dedra front arb later if you really wanted too.

ok... so with you both saying the 22mm and 24mm are great..

help...

I'd say; if you have a lot of other de-understeer-mods fitted you'd find even the 22mm giving the car a tad too much oversteer sometimes. But if you still have, say the battery up front, you'd be very ok.

But to say the Whiteline 22mm is a "straight fit" is stretching the truth a bit..

Depends how you want the car to handle and how track/road orientated you want it to be.
The bigger bar will make it understeer less by giving the rear less grip,which you should only really notice pushing hard on track days, I don't think your fully exploit this on the road.( i have not tried the 24mm)
Sparco is using the 24mm with std front arb at totb and still getting understeer,which is the nature of the car.
as mentioned above you have to get the brackets made up for the 24mm where the 22mm you can use the std brackets.
If you go for the 24mm and you dont like the rear bias you can add a dedra front arb to give you amore neutral overall flatter handling car.

I have Dedra front ARB & whiteline 22mm rear ARB, the car is pretty neutral. Very happy with my setup.

Marco this is really good question!

I have almost the same setup Koni & Eibach Pro Kit and have no idea which ARB is the best for Coupe.

i want to be able to drive the car to its limits... of course the coupe is know for its understeer...

i want to keep the front arb the way it is..

i cant find a deda front arb for love nor money.

i may just go for the 22mm rear, it seems to be a well balance set up.. i dont want to put a 24mm on the rear then have to change the front to a dedra arb to keep it in line!

There is one for sale currently in parts for sale

think thats sold mate..
plus i cant be arsed to change it!

that's my set up, but incudes Nigel's front lower brace and the standard Plus brace....i have a lot of difficulty pushing it out of line, and like taffy i'd say the whiteline rear arb made the most noticeable difference

you sick man..

Me sick?????

There's a simple answer....

A Novitec 23mm rear ARB

That's what I have, although I can't remember the last time I heard of one for sale

Personally, I'd go for the 24mm and then use other measures to control the onset of oversteer. I actually don't think the 24mm will eradicate understeer, especially on power, but it will make the rear end move around when you lift off mid bend.

Simple tracking and camber settings will make it all stable again though

Quite keen on getting at 22mm bar but where and how much...dont need any oversteer thats for sure..

My setup will be billes and eibachs plus uprate arb.Wishbones etc only done about 1k.

Could poll for a group buy via balancemotorsport?

Im up for a 22mm whiteline rear ARB.

as a comparison i paid £125 for mine

Cheers proccy.Will do some enquiring.

There around £115 from balance motor sport!

Can you do the polling in the GB section so we can keep this on track!

@ Nigel, say I go for the 24mm arb, what other things could I adjust to get things moving correctly?

Tracking - easily sorted..
Camber - ?? What setting do you think will work? -1 degree?? Or more?

Take in mind it will still be my daily driver and I would like a set if tyres to last!!!

For street/occasional track: camber -1.5deg, I think -1 is std (on std ride height).

edit: thanks Nigel, -0.5deg std camber.

also if you go for the 24mm one there's a bit of firtling about trying to get them to fit, whereas the 22mm is i believe a straight fit (pretty much)

Marco - you can play with camber and tracking, as well as damping in order to adjust how the car behaves

Per - standard camber is -0.5 (but with a tolerance of +/- 0.5)

Proccy - my 23mm ARB required some 'persuasion' to get the rear brake compensator bracket to fit, but that was about it. A 22mm would be easier, but I can see that a 24mm might require some more serious adaptation of the compensator bracket. IIRC, that's the only bracket - the ARB doesn't mount to the body/chassis in any way

Marco - go for the following:

22mm arb - it's easier to fit, and will do the job fine. Also you do not have the stiffest suspension in the world, so you dont want the back too solid.

for a daily driver go for -1.1 or 1.2 degrees on the front, and also go for half a degree of toe-out.

Right before I go crazy, I'm buying a 22mm front arb.

Now tge front arb, I'm right in saying it's 23mm yer?

What size is the dedra front arb??

The 22mm is much easier to fit, and does not do any nasty to things to the handling,
I have a brand new Dedra front arb collecting dust in my garage,I might sell at some point! (depends on what poundage springs i end up with)
I think its 25mm +
like suba said 1.0-1.2 neg camber,but i dont like toe out personally,I would keep the std 2mm total toe in.( try it and see)

The toe out really helps turn in.

but it makes it less stable,and i don't feel my car needs to turn in any quicker!
But like i said its personal,so Marco should try both.

If you want a stable road car then there is no point stiffening the rear end to make it move about rather than understeer!

just change the rear to 24mm marco, the better dampers will control the changed spring rate in roll. Leave the front alone.

I have driven both back to back in 2 seperate cars to the limit and beyond. There's not a lot in it. 22 or 24 is a decent improvement over standard. I'd go for a 24mm as the overall handling was still to understeer if you just pushed on. But it gives you a little more scope for swinging the back around if you want to.

TBH both cars had various other differences in the suspension and the car with a 22mm bar out handled the other because of the rest of the package

If you drive only on the road a 22mm will be fine. I cant see anyone pushing the car enough on the road to really say they need a 24 over a 22.

Id leave the front bar alone

What is the diameter of the Dedra front arb?

What is the diameter of the standard 20vt front arb?

The dedra is about 25-26mm(i have not got calipers).
Suba, maybe "unstable" is the wrong word to describe toe out,slightly more "nervous" would be a better description, also I think it makes the steering feel lighter,which is not desirable in my mind.

Yep - that fits. I spent ages getting my coupe to feel like that!

guys, im really going crazy on this...

forget fitting and every thing else.. lets look at just whats better...


22mm rear arb
3 people


24mm rear arb
3 people

24mm arb + Dedra front arb
1 person

22mm arb + dedra front arb
2 people

right... not getting any where quick lol
3 & 3 for the 22mm and 24mm rear arb's.

ive decided to hold off buying one today and going to see how this thread turns out!

Again, I think this depends on the various mods everyone uses..
If you aim for a full racer Coupe then you'd advice the 24mm+Dedra, if you're the occasional trackday entusiast you'd be happy with the 22mm rear ARB.
My 5 cents..

well at the moment the car is used for my fun!
i play wsith it nearly every day, enjoy driving it and when i can and its safe push it to the max.

this year i plan to get more track days in.

but i would also like to get it to the stage where i could turn up at TOTB with out worrying my spec is not on point.

i do understand its all down to choice, but luckily, people have been there and done that so im in the best palce to get the right info for one of the best set up's with out spending £2000 on Gaz coil overs!!

for me the best test of this set up will be in spa...

There is no right and wrong answer - how you get the car to behave is down to personal taste.

I would leave the front bar alone for now and go 22mm on the rear - play with the alignment, and if you feel that the front is too sharp, or that there is too much body roll, then go for the front bar as well.

i was expecting an answer like that...

im not going to play with the front bar.
The only way i would do that is if i was going to buy the Eibach kit... but i cant afford that at this moment in time.

the problem im also having is getting brilliant advice from well trusted people...
BUT some are telling me 22mm some are saying 24mm

all of them can drive and know how to set the coupe up for track and road fun.

and i trust all of them.
decisions decisions....

personaly im tempted by the 24mm...

i think i need to kit the suspension first and see what the car...
if i feel a minor tweek to the rear then a 22mm will be the key.. but if it needs more work, then of course 24mm and if it still needs it more...

come back and ask you guys what else can i do lol

I'll simplify it for you:

1. 22mm - easy to fit
2. 24mm - pig to fit

result:

Both will do the job.

As well as Suba's advice, you also need to consider than a 24mm rear ARB on completely stock suspension would probably be too much and you'd have a very twitchy car, especially when lifting off, mid-bend

So - here's my recommendation:

If the suspension is staying stock, go for 22mm

If you're fitting uprated shocks AND springs, go for 24mm

Nigel, im going for Koni socks and eibach springs!
standard shocks are a bit too boring for me!

fitting will not be that bad, i will be doing it on a ramp at my mates garage!

so looks like 24mm will be the better choice of the 2!

I would say so, but that's only my opinion. My car still understeers with a 23mm rear ARB and a standard front ARB, so if I had my choice again, I'd go for 24mm

However, I can get the rear end of my car to step out if I provoke it a little. Because its set up to be neutral, its all very predictable, but if you go too far, it can become unpredictable, which is no fun, and just slows you down, as you've no idea if the car is going to grip and turn, or just spin.

You'll be fine with Billies and Konis and a 24mm ARB

i see what you mean Nigel!

i think the choice will be a good one!

of course Nigel if your not happy with your set up and fancy a re-sprayed sprinty with a zender kit, i wouldnt mind swapping for the moonie!!

You'll never dial out the understeer completely, there is just too much weight in the nose of the car.

You're right about keeping it predictable for road use - I have no doubt that I could drive my old 20VT faster on some B roads than my RX7 - primarily as it was much easier to correct when it started to slip, so you could really go for it.

And just to confuse the issue even more, Marco ...

I had a 22m rear ARB with standard front ARB and it was very neutral and very predictable.

Of course it still understeered at the limit (or lift-off oversteered if provoked), but (as such) as massively easy to drive very quickly.

[It's fun this, isn't it? We could keep him from ever buying a new ARB ]

LOL!

Oh FFS sake Dave.

I loved the feel of your car.

No no I'm staying strong and buying a 24mm rear arb.

Dave your welcome a go in mine to see what you think!!

but hurry up Dave, he'll have smashed it up in no time

LOL proccy!

Me crash proccy!?

Suck my nicely shaved plums!!

I found it. Front arb is 23 mm.
Rear one is 19 mm.

I second that!

Quick question:

What size is the standard rear ARB and roughly how much extra strength (springyness/force) does the 22MM provide?

Thanks

Look two posts up from yours ^^^

just to put an end to this one!

im buying the 24mm rear arb!

thank you and good night!!

Is that your final answer?

Are you sure?

You sure you dont want to phone a friend.... oh no wait....

He'll change his mind yet ...

Or complain about being broke ...

seriously!!!!!


Yes..

YES

WOW dont you start!!!



no Dave, not changing my mind!!!

but i am broke!

and just before Hovedan starts....
Yes i will be there for the track day!

but if you are not wanting the expense of fitting a front one at some point if you find it cuts loose at the back much easier..then the 22ml is the better one ..also it will cost more fitting the 24 having to have brackets made etc..i would have another think about it if i was you .. i thought the 22 ml was the best bet if not touching the front..plus its cheaper,plus cheaper to fit..

NO...
lol

im staying with Nigels Recommendation..

then blaming him if it goes wrong lol

A rear ARB can't actually go wrong - it will just be your inability to drive the car properly

You cheeky git!

LOL - there's nothing wrong with a bit of sharp handling, although it can be a bit of a surprise when you've been so used to terminal understeer

My guess will be that for the first week of having the new ARB, you'll be constantly steering too hard and finding you're having to back off the steering input

Yer, Im expecting positive things from the arb!
I'm Doing the suspension first leaving it a wek then the rear arb ao I know what difference it really makes!

As I know your speaking from experience, I will expect exactly what you said lol

come on you

nearly 1000 reads to watch you poncing about with arbs, ffs - do you italians ever make a decison???

yes, and Marco get yerself booked on the Donny track day, an ideal opportunity to test your new suspension.

That's the plan mike!

Good man - do it, there can't be many places left now fella

i think there were 3 left after i booked thursday night, so get a move on marco!!

There on negitive figures now. don't know what that means

Does not matter any way.

The car is Fu**ed.