I was having a discussion with some members in my local SCCA club (non-mini drivers) that were saying a very big rear swaybar has the potential to be slower. Like many other short wheelbase cars my inside rear tire is off the ground in most turns. Wouldn't that mean that too much rear swaybar and being really stiff is losing too much traction?

Would it be better to have that inside tire still on the ground? Or am I loading the outside tire enough to makeup for the traction loss?

I am running the JCW suspension with an H-sport competition rear swaybar on medium.

I need to do a test and tune event next season and play around with swaybar settings to see which is actually faster...

 

Not every car reacts the same. Like you mentioned, they're not MINI drivers. The good thing about most of them is that they're adjustable. If you wanted to put forth the effort, you could always give the car a good run as-is, then adjust it down to the lower setting and see how you like it.

 

These cars understeer quite a bit, I don't see how an upgraded rear sway bar that eliminates that understeer could be a bad thing. You can always have too much of something, but in general, I don't see it HURTING more than helping.

 

Slower with a rear sway bar on a MINI If that happens your doing something really wrong

 

Way, would you personally be faster the stiffer you go with the H-sport? I don't have anything to judge by as I have been on the setup all season and this is my first full season. I have taken first or second in PAX all season and will likely take the top points overall for my club this year. Just one more event to go. I am tempted to do simple mods and run STX in my club next year. I am also thinking of trying to make it out to nebraska next year. A few guys in my club go and place mid-pack or just a little better.

 

My opinion, novice though it may be, is that you need to feel comfortable with the balance of the car. If you like the way the car rotates on an autocross track, and sometimes that means its lifting a wheel, then you will drive faster/harder. The ultimate judge is you, and what you like, and how you like your car to drive.

In the 'post pics of your mini' (or something like that), Charlie posted a pic of his H/stock cooper lifting the inside wheel. He is a nationally competitive.

Have fun,
Mike

 

We lift the inside rear wheel and we're on the stock (sport) suspension. Its going to happen anyway. There is a theory that that's a good thing.

I'm suspicious of reducing rear grip to get oversteer, so I'll be interested in your conclusions ffrom test and tune.

 

If we were putting down power to the rear than yeah lifting is bad, but most Mini drivers try to get the car to rotate as predictably as possible. Some even go so far as to run less grippy tires in the rear to encourage this. The quicker we can get the front wheels pointed straight, by getting the back half of the car around the corner, the sooner we can put full power down.

 

Yes I'm faster with it stiffer. Looser is Faster.
I'd recommend running a national event. You learn a lot about how good you really are. And you learn a lot about how an event should run. I find many local event run very lax on rules, and timing. National events tend to be run very strict and in a timely manner.

 

I'd bet the guy telling you that your sway bar is going to hurt your times and you should take it off runs in the same class as you? lol

 

2012 R56 Justa
RTFHS (now HStreet for 2014... yay! Level heads prevailed!)

Strong National, local driver, and Evolution instructor. Finished 2nd in RT2 at NJ ProSolo in April.

OEM Sport Suspension
Alta 22mm rear bar - all else OEM
R84 wheels with 205/50/16 Direzza Z1's (got two seasons out of them 2012, 2013)

My $.02 on the matter... In 2012, the rear bar was full stiff, as most people set the big bars to help the MINI rotate. Every so often while trailbraking into certain corners, I'd experience the brakes getting real hard and going into ice mode. Photographic proof showed the inside rear tire of either end was in the air more than it was on the ground through more corners than I cared for. It was bad enough that I would miss my turn-in points by 5 or 6 feet as I hoped the car would slow down as I wanted it to... But the brake was as hard as a rock and the car wouldn't slow down.

We determined that what was happening was the wheel speed sensor for the ABS system thought the wheel was traveling zero mph. So, I softened the bar to its softest setting and only have the issue once in a blue moon.

Long story short... A big rear bar can ABSOLUTELY be too stiff.

 

And the car is still rotating enough for you on soft with a 22mm bar?

 

k_h_d, do you have a Coupe or HT? A Coupe will take considerably less RSB to get to rotate. Also some like to use tire pressures to dial in the rear. Also the width of tire and stickiness of them will impact setup. My 245 r-comped Coupe needs a different setup than 205 street tired HT Justa. If you are confident and comfortable with what you have, then stick with it.

 

Adjust tire pressures at the autocross and try different alignment settings.

I don't mind loose cars, as evidenced by my regular codrives in my friend's CP Camaro...
However, without a 500hp Z06 motor to make things interesting and regain lost momentum, ummm, rapidly, I prefer the MINI to be a surgeon's scalpel, especially through transitions. Therefore, in faster slaloms (28+ paces cone-to-cone on a course walk), I prefer the rear to stay in line because that's where I'm making up time compared to most people and it's where any MINI begins to jump up in PAX.

 

You can always over do something, the OP sounded like he was saying upgrading the rear bar at all would cause negative results per the guy who he was talking to.

 

You're probably never going to be able to completely eliminate lifting the inside rear wheel. Our car does it still but very rarely. The reason you're lifting the inside rear wheel is a combination of soft springs and a stiff rear bar.

Everybody talks about how bad these cars understeer in stock form. I never really thought it was that bad. Certainly nothing that I couldn't drive around. I could get the car to rotate when necessary. Could have been our alignment/tire pressures helping out though. Although our other autocross car is a STI so I'm used to mitigating understeer

My personal problem with big rear bars is that they tend to make the cars kind of "snappy". Great for low speed stuff but quite tough to drive at the larger/faster courses especially though quick transitions.

If you have the opportunity to do a test n tune definitely play around with the rear bar and also tire pressures. If you have the knowledge/tools you can also tune the oversteer/understeer really well with rear camber.

Whoa whoa now. 245s? Hoosiers? Pics? I didn't realize people were fitting more than 235s.

 

At our sunday autocross I had NO problems getting the rear to come around. It was rainy and wet and my rear end was all over the place. Spun the car once and slide the back through one turn repeatedly.

I am running JCW springs, shocks, standard front bar and H-sport rear comp bar on medium setting. Tire pressures about 40psi in the front and 30 psi in the rear.

 

i would recommend getting an adjustable shock so you can change the stiffness to dial it in to something you can handle if its too loose for you.

also, when the rear swings out on you, you have to accelerate to transfer weight to the rear to stop the slide. it is very counter intuitive at first.

 

An interesting tale - thanks for sharing that one.

Cheers,

Charlie