Hello,

I was hoping to get some help from some experienced track drivers with the r56 MINI S. I had my first track day yesterday at Pueblo Motorsports Park. I had a blast, and it is shocking how capable the MINI is (that is a big compliment because I had an E46 M3 prior to the MINI)

My question is this: What do I need to do to get the car to rotate better, and not understeer so much? I was running the car bone stock (I do have a stock sport suspension) with run flats, and I really think the hard run flats were the biggest culprit, and I was running about 43psi on all 4 corners (which quickly got over 50 psi after some hot laps). Would better track tires do the trick, or does the r56 really need a bigger rear sway? What about tire pressures?

I don't want to go overboard with mods, but I was hoping there were a few tricks people had tried to get the r56 to rotate. Overall though, what a car!

Thanks---

 

I have a R53 which has the same problem stock. I installed a Alta 22mm rear anti-sway bar in place of the stock one. I've got it set to the softest setting and that pesky understeer hasn't been a problem the last couple of times I've autocrossed. Never had it on a real track though.

 

First off - GREAT to see an R56 on the track... I have yet to see one in person on the track :(.

First off - your pressures seem quite high. While run-flats are not ideal, I have used them on the track when I first started out and they were fine to get used to driving on the track. I would maybe try 35psi so your ending pressure when you come off the track is about 39psi. As you get faster, you will need to start the pressures a bit lower since you will heat up the tires more. Ending pressures over 39psi are high in my opinion and will make the car drive like crap.

As for rotating in a turn - there are a few ways to accomplish this. Unfortunately just adding mods will not fix this unless you know what to "do".

Think of how your car's weight transfers from front to back depending on accelerating or braking. When you accelerate, your weight transfers to the back, making the rear tires stick and not slide. Braking or lifting the throttle, transfers the weight to the front, allowing the rear end to get light and easier to rotate.


Given those 2 scenarios, when you come to a turn, try threshold braking (hard braking in 1 short, HARD, push of the pedal while in a straight line) and just as you release the brake, slightly turn the wheel the direction you want to turn (also known as trail-braking). This will not only get the rear end light, but will also rotate it where you need it to go.

Once you are pointed in the right direction, get on the gas to transfer your weight to the rear wheels and stop your rotation. It is a strange feeling at first, since it will feel like you are about to spin out, but if you nail the gas and stay in it, you will feel the car pull itself out of the turn. Having DSC off when trying this is probably a good idea since having it on, may not allow you to have the power needed to pull out of the turn without the back-end coming around....

Here is a video where this is taking place at my last track weekend 2 weeks ago:

http://www.motoringfun.com/2008/04/2...nd-2008-recap/

Hope this helps!

 

this will help your car rotate

http://youtube.com/watch?v=U2S7L9HpvlE&feature=related

 

I'd recommend either an aftermarket swaybar or running your tires pressures slightly lower in the front than in the back. On my last track day in damp 60F weather, I ran 37 psig (front) and 39 psig (rear).

I'm not sure if the differing tire pressures are going to have an effect since your running on the RF tires. On normal tires the slightly lower pressure in the front tires will cause a (very) slight deformation of the tire resulting in a slightly larger contact patch -> more grip in the front compared to the back, causing less understeer.

 

Easiest thing to do with a stock car is to play with the tire pressures. I don't know what would be a good range to start at as I have yet to get my R56 to a track but I would wager that 36 psi front and 40 rear would be a good starting point. You would have to make changes from there but it would be the easiest way to get the car to rotate without buying any other products (which you will probably have to do anyway...).

Also, for a track day, as I am sure you have realized after you experience, nitrogen filled tires is very helpful.

 

Try the Auto-x'ers trick of marking the tire with chalk, shoe polish or a tire crayon. Mark the shoulders where the tread meets the sidewall. Talk to some of the experienced drivers about what kind of rollover you should be seeing; you can then start adjusting your pressures after each session in order to zero in on the right amount.

Once you dial that in if there is still understeer try adding 2lbs to the rear at a time to see if that helps.

I don't know your driving style or the feel you are looking for but this is how I would go. Add a 19mm bar to the rear and try it medium and then hard settings. If thats not enough you can always sell it here and try a 22mm.

Thats my 0.02 cents.

 

I've been fiddling with my car a bit. I've not autocrossed it yet. But I have done serious autox in another fwd car.

I think the thing you'll find is that you drive a fwd car different than you do a rwd car. Its a different sort of athlete than a rwd car.

I still get suspicious of replacing the rear swaybar. Though if you only did track days on a big track this may be the route. There are so many things though that opens up the worm can on.

So, the easiest thing to fix is your driving. My two cents is that an fwd car is just going to understeer a bit. So what you're going to want to do is drive 'slower' and on a slightly more compact line than if you we're ripping around in an M3 or similar. you'll be felling like you're waiting for the car a bit, but your lap times will be faster on a track and for autocross.

The next thing you can do in the mini setup stock if you absolutely have to rotate it is the following:
1. set the car and use trail braking. She'll rotate.
2. Set the car, lift throttle and very gently increase the radius of the turn before you feather in more throttle. This is pretty much just like trail braking, but you can't overcook it and try this or you'll understeer. you must be gentle.
3. Try a really different line. If you're understeering everywhere on the track you might be too early on every turn. On a proper line the car would probably be a better dance partner. Look for a short line, set the car and go. Don't feed in a lot of steering or you'll not be able to get back on the throttle. So be patient on the entry and you'll come out better. I said it might feel slow, but I didn't say you'd actually be going slow. You just need to drive the car in a way that feels right to you, but also appeals to the laws of physics.

setup wise I don't think the basic parameters of the stock car would do very well with R-compound tires. I think the first thing you'd have to do is redo the front sway bar, and get new shocks in order to work the tires and keep the suspension geometry correct (and the rear wheels planted). Just my opinion since I actually haven't opened this can of worms yet.

Good luck.

 

I do a version on that theme but I measure the tire temperature at three points along the contact patch --- I look for a uniform temperature of about 180-190 degrees after hot laps.
Too hot overall, add air; too cold, let it out.
Too hot on the inside, reduce negative camber; etc.


The first thing that I'd do for good track performance is get rid of the Mini (heavy) wheels and tires and get someting appropriate for the track. A set of 16" Motegi Tracklites will weigh about 12.5 lbs compared to your 25 lb Mini wheels. Add some quality rubber and you're already doing better.
Next, I'd put on the Hotchkiss Comp antisway bar.
Then some Cross or Billi coilovers, camber links if necessary.
Last two items, DDMworks CAI and Way Motor Works turbo heat-shield ---- cooler is better.

 

I don't have tons of R56 suspension modification experience (mine's stock). But, I've driven a bunch of the first gen cars with different levels of suspension work done to them.

A big rear bar will remove understeer. But, it's not very subtle. Cheap, easy, but not a great answer all by itself. It can make the car a bit of a handful at the limits.

Camber plates also remove some understeer, but by adding grip up front. Unfortunately, camber plates alone may not allow you to add enough camber to make the car neutral.

The best answer I've experiences is camber plates and a medium sized rear swaybar. You should be able to get the balance of the car where you want it with that.

Then, add springs and dampers to raise the cornering limits without changing the balance much.

And, yes, the driver does need to be "upgraded" also. But, my stock R56 is one of those cars that just does not rotate. I've had a few other drivers, who are better drivers than I am, try to get it to rotate on a figure 8 skidpad, and it just isn't quite there stock.