I have been enjoying my '12 Mini S hatchback and especially on club "runs".
This is my second r56 and, this time, I bought it without the sports suspension and 17" wheels. I was wondering if it would be a good idea to buy a stiffer rear sway bar. Would I notice an improvement in handling?

 

Yes

 

Would a 19mm be the right size for my car, mostly regular street and monthly club runs?

 

19mm should be good for the street. Do a search on this site and you'll find a bunch of useful information.

 

Thanks for your reply. So much of the discussion is about springs and sport suspension. I really like the std suspension for everyday driving. So, I am looking for response for my setup.
Don C.

 

A sway bar is going to be your best option. You won't even know it's there until you start hitting the turns. It will make a HUGE difference (positive) to the way the car rotates in the curves.

 

It is a difficult question to answer because everyone has different expectations. I started with the sport suspension which has an 18mm bar. I went to the 22 and started on the softest setting. That was a huge change. I lowered it next, did the free camber mod, got an alignment and went to the middle setting on the 22mm and the car is really balanced. It definately does not have the tendancy for the rear to come around.

On the clubman I went with a 19. It was starting from std suspension which was 17mm. It's a little soft for me on full stiff and still understeers but a definate improvement over stock in controlling body roll, allowing you to push harder. I don't have more suspension plans on the clubman. I do on the cooper.

To go from a 18 to a 19 some may say will not make a large enough difference. And that is where this becomes a difficult question to answer. Are you looking for a small tweak or a pretty drastic change? Is this going to be your only change ever or are there more suspension mods in the future? The sway bar only affects cornering so you barely notice in daily driving . . unless your roads are like LA which are pretty much the equal of a third world country (and is the real reason SUV's are so popular here), then you may notice more side to side rocking with the stiffer bar. Some people swear by custom alignments, "custom" meaning a race shop will have to do it and some extra parts to make your suspension more adjustable will be needed. You will also need to get used to driving with the sway and tire wear may not be the best. But on a bumpy road this is the fast way to go.

 

Thanks for your replies. It looks like a 19mm bar is the way to go. Is there any difference from one brand to the next in the same size (19)?

 

I have not put it on because I just got home from MOTD but I got the Hotchkis 25mm bar. It is holo so it weighs less then the stock bar but stiffer but not to stiff. 22mm might be a good idea or maybe the Hotchkis bar.

 

I second that. I'm buying a H-Sport in a few weeks.

 

I got an Alta 22mm bar last week and having driven the Dragon with it this weekend can highly recommend it!!
Made a huge difference in cornering... Got it set on the middle setting. I don't think it's needs to be any stiffer than it is, but I've got Koni shocks, adjustable rear camber and H&R springs fitted too.

Remember though, if you are mainly driving highway, you may not feel the benefit of it.
I'm in WV and I don't think they know what a ruler is when building roads!

 

Adding a rear sway bar, or replacing an existing bar with a stiffer one, will change the handling of the car. Which is certainly the point of doing it. But the result may not be exactly what you want--it would be best to drive a MINI with the suspension you want already on it. That will let you feel how the car handles, and what the limits are.

A stiffer rear bar will help the car to rotate, but it also means that there are more circumstances where the back will want to step out, or even try to swap with the front end. If you're good with that and know how to deal with it, this can be a good thing. If you're not prepared for it--if you're used to the stock handling, for instance--it can be a recipe for spinning on your next on-ramp.

An adjustable bar can help let you tune exactly how stiff the rear gets. Testing can help determine the effects of each adjustment, and can help the driver learn how to react to the car's handling.

There is almost never a universal suspension setup that is ideal for all drivers. So do what you can to make sure the setup you are getting is one that is good for you.

 

Going from 18mm stock to 19mm aftermarket is a bit misleading if I recall. It doesn't sound like that big a jump, just 1mm.
Middle setting for the Alta 19mm is 40% stronger than stock. Highest setting is 77%. Now that sounds noticeable. (Numbers from Alta site)

I have the Alta 19mm. Middle setting feels the same just cruising. Really great if you get feisty on the street. I think you would be happy with it.

 

dcompt - depending on your budget, you may want to also check out the Eibach 19mm rear sway bar as well since it's very competitively priced on eBay. I've just installed mine - a definite improvement from the stock 16mm on my "justa". It's made a significant difference in cornering while keeping its street manners, in my opinion. It has two points for adjustability - I'm running on the stiffest and it's working well for me. 22mm would be too much for me ;-)

 

Alta bar here as well, definitely a must.

 

If the lengths and materials are the same, the stiffness of a torsion spring (that's what a sway bar is, a torsion bar that connects the two rear wheels together) goes up with the fourth power of the diameter. That's 19^4 (130321) / 18^4 (104976) = 1.24, almost 25% stiffer. So no wonder there was a sizeable change in feel.

 

Indeed...1mm may be noticeable especially if you use a stiffer setting. That said I've noticed first gen owners (like myself) are generally more happy with a 19mm and 2nd gen owners are more happy with 22mm bars.

There's also a 20mm adjustable Whiteline bar that is quality and could split the difference.

Someone mentioned custom alignments and IMO a good alignment is a must have for these cars! I run -1.7 degrees camber up front and -1.3 camber rear with 0 toe front and a tiny bit of toe in rear. I use adjustable rear control arms (h-sport is good) and IE fixed camber plates. Perfect tire wear. Makes more of a difference than a rear bar IMO. You might be happy with just the free camber mod.

- Andrew