I have noticed that the number one suspension mod everyone mentions is to first get a bigger rear anti-roll bar.

Forgive me if I get this wrong, because I probably will so bear with me here. Why? I am only talking about street driving, no racing. If I'm wrong, tell me

At the limits of adhesion in a corner, whether the car understeers and plows straight ahead, or oversteers and the tail comes out ... in neither case are you going to go any faster around that corner. Unless you are used to say rear-engined, rear drive cars and the tail come around, I would imagine the "normal" driver might have a bit of a fright (to say the least).

Since I'm sure that most normal driving is not done at 10/10s, whats the point of changing the characteristiscs from understeer to oversteer (althought I agree neutral is best). Why bother?

In other words, If you just do some spirited driving around town, there is no way your going to be at 10/10s all the time around corners so why the sway bar change AND wouldn't be a bit safer to ensure the car is NOT oversteering?

Just wondering. Like I said, I'm probably wrong so correct me.

thanks, all opinions are welcome

 

I just couldn't find anything better to do that day...

 

I've had my rear sway bar (h-sport comp) for over a year now and it definately transforms the car on/off the track. You will eliminate the plowing built into the car from the factory and neutralize the cars handling (on the mid setting) For normal sprinted driving it will feel like the car turns in quicker - pivots from the center of the car and the rear end sits down alot quicker when you are throwing it around. I recently took my buddy's MCS for a session at Mt.Tremblant to see what the difference is with out the bar. OMG! Without the bar the car plows through everything and the front tires do so much more work. The rear end of the car also much more active and you have to wait an extra second for it to sit down before the next turn. It really transforms the car. I am so used to my car with the bar that i forgot how much of a difference it makes. I really had to work the car to keep up with mine. Best mod for sure!! On the MCS the h-sport comp does not have any bad habits and even in the snow the mid setting is safe to drive. You can actually do real doughnuts in the snow as the rear tires will just follow the car around if you pull it into a tight circle. If you throw the car through a corner you will only get a nice drift going.. no more plow! and the rear end will only step out if you are carrying too much speed.

phil.

 

Thank you for your description

I fully understand the transition from understeer to oversteer but thats not what I'm asking. I'm asking, whats the point for street driving? The limits of adhesion are based on your tires (I believe) so either the front tires will start to skid (if oversteering) or the rear tires will start to skid (oversteering) but in neither case are you going any faster (if thats not true, someone tell me how please). I understand why you want to "set up" the car in a corner while racing but like I said, your not driving at 10/10s normally.

So, for example sake, would I want my wife, who drives the car, to come around a corner to fast and find the rear end coming around, or just plowing straight ahead (thats a bad example because she's drivin mid-engined, rear-engined cars all her life but I'm trying to make a point)

 

What's the point of buying a MINI?

ok, i will shut up now.

 

I have an MCS with a 22mm RSpeed rear bar, for normal street driving it's in the softest setting. The car is very graceful while cornering, and seems to steer more from the center; it's not at all unbalenced or hairy.

 

I use a bigger rear swaybar not to move from understeer to oversteer, but to move from understeer to less understeer. I do believe that this lets me get through corners faster (on the track / autocross course). On the street, the bigger rear swaybar is not needed.

 

For street use it does make the car neutral - really nice for sprinted driving. I think the best way to make your decision is to drive the cars back to back.

phil.

 

I’ve read many times on this forum that anything less than a 22mm effective rate is useless. But, I’ve been there and done that and discovered it’s more of a good match between springs, struts, bar and driving conditions that determine usefulness. I’m using an 18 mm bar with some moderately stiff springs and it’s a great match for my roads.

Yes, a larger bar can be fun and it can also have a learning curve to become adjusted. One way to lessen the tendency for the rear end to come around while using a stiff sway bar is to add more negative camber. You will have to experiment (invest time and money) and see if it fits your driving style.

 

Think of it this way: in the factory setup, the front tires are overworked and there is grip to spare in the rear. A bigger rear bar transfers more of the work toward the rear by taking some of the load off the front, which allows the front to then do more work when you go faster (At any particular speed in a corner there will be a specific amount weight transfer toward the outside 2 tires as the car rolls. If the overall spring rate in the rear is set higher, there will be more weight pushing down on the outside rear tire and therefore less on the front tire. Spare grip will then be made available in front)

Better balance lets both ends skid at the same time and this extracts the most grip possible from all 4 contact patches. So it can let you go faster.

 

Another way of looking at this is by analyzing skidpad numbers, and, balance. Lets assume we have two cars that corner at .9g. One corners with mild understeer and the other corners with a neutral attitude. Each car is equally as fast in steady state cornering. However, once you introduce straight portions of road and other transitions, the neutral handling car will be faster. Cornering power, and, balance defines speed in the real world or on a race track. The neutral handling car will be easier to set up going into a straight from steady state cornering as well as into and from other transitional areas.

Steady state cornering is but one part of the cornering picture.

 

First of all, I am an advocate of learning how to drive what you have, rather than throwing money and parts at a car (and of course having said that I'm thinking about changing my H Stock autocrosser-Mini into an STS autocrosser-Mini, so it's not like I follow my own philosophy ).

But, beyond that, in prinicpal the big rear swaybar is something that you'd notice (typically in a good way) without all the hero-driving that people like to talk about. As BFG9000 said, it will keep the front end more planted so you can use the gas more, and it will make turn-in even crisper (not that the stock Mini lacks much in the way of turn-in). These are actually the real benefits of the big rear swaybar. Oversteer is slow and bad just like understeer, although admittedly oversteer is more fun

 

Thanks for your clear and thoughtful explaination.

 

Or you could say, "if I have to explain it, you wouldn't understand."

 

hehehe, I can't believe people are responding seriously to this topic.
maybe I've been around too long.

 

For those of you who tried to answer, thank you very much. I see and understand some of your points and appreciate the time you took to answer.

If you don't think I "get it", maybe your missing my question.

thank you

 

Kenchan, you're such a teaser!

 

Very interesting discussion...I am glad Chows4us brought up the question.

I learned alot from everyones comments. (esp BFG9000)

Is is possible that a bigger rear bar would also help even out tire wear for a Mini on the street?

Steve

 

Tire wear is determined by many things not the least of which is weight bias and drivetrain layout. It is true that weight will tranfer to the outside rear wheel a bit more with a larger rear bar, but at the same time weight is removed from the inside rear wheel.

Camber and toe settings will affect tire wear more than sway bar size.

I drive 112 miles round trip every day to and from work. 98 of these miles is on the highway where a larger rear bar isn't helping with any weight transfer.

 

I think to help a person appreciate a larger sway bar one needs to ride/drive a car with a larger bar

My car is totally different in its handling from stock to my Alta 22mm. Bar is currently on the hard setting which creates some oversteer...I know I need to take the time to change it

 

I, too, have often wondered whether a rear sway bar was a worthwhile investment for a daily driver....first you get the sway bar....then you need grippier tires. Not sure I even want or need to go there. I do have some nice corners on my daily commute, but to take them assertively would eventually get me in trouble...w/ the law or, at least, my fellow motorers. I've opted to leave things stock (for now) and enjoy what I have.

 

Without beating this discussion to death - as I have done before in other threads - match a swaybar to your driving venue. A 19mm rear bar with a stock front bar may be all some of us need for general, albeit slighty enhanced, driving pleasure.

 

As for the argument that it may not always be useful for street driving, I will postulate that: More cornering grip is always better, for the same reason that shorter stopping distances are also always better even though you may not always use it--it gives you more safety margin just in case you need it.

Yes, a little understeer is best if you aren't paying attention/prepared to catch the rear end, but for street driving I figure I'll be driving with DSC on anyway:smile: so I have my 25.5mm bar set at full stiffness.

 

...and for those of us without DSC...

You actually bring up a very good point BFG9000. I do not have DSC. I would suspect that DSC might allow one to use a larger bar without 'some' of the nasty over-indulgent affects.

A 25.5mm rear bar is indeed very large, especially for the street. How does your car feel on long fast closing sweepers at triple digit speeds?

 

You do not have to drive the car at its limits to feel the benefit of the bar. To me the car just rotates more from the center and feels more "balanced" ......a real pleasure to drive. I don't know if you ride bikes or motor cycles or snow ski. but to me when my equipment is dialed in it more pleasureable at any speed. It makes the car feel more like a "sports car."

THis is not a technical explanation but I don't think equations when I drive.......I just like to "motor."