I currently own a '12 hardtop S and plan on doing 1 part at a time and test at the local AutoX or track day.

My previous car '10 Evo X GSR, which I did a mild upgrade with, didn't turn out so well.

I first did a cup kit (this was a recommend matching of sway bars, bumpsteer correction kit, and springs) on my '10 Evo X and had it set-up by John Mueller (a Evo specialist and racer), which included front and rear sway bars set to hardest up front and softest at the rear. When all said and done we came to the conclusion that I actually lost grip and I lost cornering confidence when approaching the limit, meaning it got real twitchy and scary. Lesson learned: Don't go out and buy parts just because people say their good, buy one at a time and test.

On to the Mini (base suspension on an '12 S)

Before my first track/autox I went and got alignment done and put some Dunlop star specs on and wow what a difference, but my rear toe was way out of whack. So I did an autox event and I found out the Mini has pretty good manners when at the limit, just make sure you don't cook the entry and the car will rotate nicely. I don't like to use the word neutral because each person has their own idea of how a car should feel and from my experience a car is either rotating or pushing. So now I have a good base on how the car feels.

So now I added an Alta 19mm RSB on the hardest setting. From my understanding and correct me if I'm wrong, you want to find a balance between the front bar and the rear bar. Luckily Mini has already given us a good starting point. The stock bars (mine) are 22.5mm front/17mm rear, step up to sport pkg and get a 23.5mm front/18mm rear, check the JCW box and get a 24mm front/18.5mm rear. Do you notice the pattern? So since I added at 19mm rear bar I should add a 24.5mm front bar to keep that balance. But, almost all cars are set up with more under-steer for safety, we can't have grandma looping her Buick on the freeway on ramp just because she lifted off the throttle can we? So my theory is to add a slightly bigger rear bar to correct this, say a 24mm front bar, hm..... I think I may know where to get one of those for only $99 /cough/Sewell/cough.

So how does the car feel? I haven't had time to get to a track but I do have some first impressions. The rear does come around better but I may want to move to the softest setting. I did a good old Norwegian flick with a dash of lift off throttle and got a little drift out of the bad boy. While this wins on the fun meter, you may find yourself backwards quite quickly on the track. I do have a favorite on ramp were the standard is set at 80mph, 83mph entry w/ a 84mph exit when stock, and I'm now at an 84mph entry and a 85mph exit with no drama and very little tire squeal (this is good). The unconfirmed record is at 100mph on a Cayman S and my Evo was at 85mph entry with 77mph exit going sideways, that's that bad set-up I mentioned). I'll leave it as is for now though . As far as ride quality, the girlfriend hasn't notice any change.

Now what does all this get you in terms of performance? Very little in my opinion. This is where we can focus our debate. First we need to be on the same page of how a sway bar works. On straight on bumps they have very little to no impact on suspension travel, once the car starts to lean the sway bar gets twisted in a progressive fashion and it tries to counter that lean. The result is less body lean on turns with out the harder spring rates or dampening. So why not throw the biggest bar on and call it a day? Now this is where millions of dollars are spent by car manufactures finding this ideal set-up. At some point you'll minimize deflection from a lateral load and will cause the tire to break traction to early. Now this isn't always a bad thing, if the car is under-steering a fix would be to stiffen the rear via springs, damping, or swaybars, in theory this should increase the rear slip angle of the rear tires allowing the car to rotate around the corner but at the cost of that deflection. What about a front sway bar? This might be a more risky decision. A stiffer front bar from what I noticed in my own cars results in quicker front bit but once you pass the apex if the bar is to stiff it will break that traction and result under-steer or wheel spin for us FWD cars.

So I mentioned deflection a couple times, maybe we can chat on that to. We need deflection in order to obtain grip. Imagine taking off rubber tires and putting on metal ones. It would be like ice skates. The rubber flexes and grabs at the ground allowing the car to not slide all over. To little deflection and we have ice skates, to much and we have mashed potatoes. Even race cars have this going on and it is apparent when you watch an F1 race on a street circuit. They actually have quite a bit of body roll and you can see the tires jiggle and move all over on those super slow-mo's. So a good rule of thumb is to stay away from super stiff. Well unless you want a low grip set-up.

So what have I learned from all this. The engineers at Mini know way more about suspension then I do. Avoid wasting money on "race" parts. Go to an AutoX or track day before putting stuff on your car, you may be surprised that your little stock Mini can punch well above it's weight and behaves completely different than when you drive it on the street. Lastly I want to add something that I heard a lot if you plan on doing a complete suspension overhaul. If performance is most important then don't buy swaybars at all. Spend that money I high quality adjustable coilovers and then you can truly have the best of both worlds, at the twist of the valve you can have super plush daily driver and then to a super stiff race set-up.

Please add any thoughts and/or opinions, we can't learn if we have no questions.


Cheers

Josh

PS: I was adding this on to a thread but realized it got very long and slightly off topic, so instead of deleting it I just posted a new thread.

 

Thanks. One question, swaybars are relatively easy enough to experiment with and determine what works best. How about coilovers? How does one determine which are best? Do you have any preference?

 

This is probably my most asked question that I have and sadly most people can't explain what makes one better than the other. From what I have deducted the best benefit is corner balancing, to me their is no reason to choice a coil over over a cup kit if you don't get the car corner balanced. I see it as a huge waste of money when people buy high coil overs and don't use them to balance the weights.

No should you go out and get a $800 set of coil overs? For me the answer is no way. I found most coil overs come with progressive spring rates and these types of springs aren't as good for performance driving as a linear rate. Progressive springs make it harder to keep the car on that knife edge of balance because, well the spring rate is always changing. A linear spring rate will make the car more predictable and will give better feedback before the car let's go.

Second it the ability to adjust the rebound and compression. Cheaper coil overs may only have one adjustable setting and some don't have any. Now why would you want all that adjustability? The main advantage I see is having a street setting and a track setting. I don't necessarily mean a comfy setting and a super stiff setting either. Tracks typically have much smoother surfaces, while streets have potholes, gutters, and bumps. A softer setting will actually give you more grip because your wheels will be able to stay on the ground better when hitting those objects.

This leads to the 3rd and I think maybe the biggest reason for price differences and that's remote adjustability. Cheaper coil overs may require you to get underneath the car to change, some even require you to take them off the car completely. High end sets can have a simple dial to twist on top of the strut or even in car adjustability. This can single handedly be the biggest reason to not get coil overs in my opinion. If your not going to take the time to dial them in, then why buy them in the first place. Even if it's just for looks, changing springs can easier and much cheaper.

Now the bad news. The only set that would make sense for me to buy is from Ohlins and those cost around $2,400.

Cheers

 

Thanks again. I had been looking at the Ohlins due to the positive feedback I've read on them but their price was beyond my budget at the time. I may rethink that now. Thanks again.

 

A few of the hardcore MINI track rats I know regret buying a bigger front sway bar. All you're getting is more push with that. The biggest handling refinements are made with a rear sway bar, more negative camber up front, good tires, and coilovers. I've had quite a lot of track time with my setup and am very happy with it. I'd like to start experimenting with my front/rear rebound next year for fine tuning.

Regarding brand choice, I think it's all up to preference when you start looking at the top of the food chain in the ~$2000 range. KW, AST, Billstein, and Ohlin all make quality stuff. Choose the right spring rates for your application and don't look back. It's just too hard to say that any one of these brands are "better" than the other. What I can undoubtedly say is that I wish the rebound adjustment on the rears of my KW V2s was not at the top of the strut. Trying to make an adjustment through a small little drilled hole in my car definitely isn't as easy as what Bilstein offers with their big *****.

 

What OEM spring rates are provided with each of those cases?

 

I started my suspension mods in the summer of 2008 on my R56 MCS, having already had perhaps 40 track days on rwd momentum cars mostly, such as the Lotus Elise etc. The mods were all done one or perhaps two at a time, also after each mod, some track time. That is why much of the garage was full of "used" suspension stuff.

My opinion is that suspension is one of the hardest things to tune for us weekend trackies. You must make the sum of the parts work well together in a tuned fashion, based on your driving style, track, conditions etc. What I like, you may not.

What I like for good initial turn-in, reduction of understeer, better handling:
Front camber between -2 and -2.5. Rear camber around -1.4 to -1.6.
Harder rear sway perhaps 19-20 mm, set around medium.
Slight drop of 1" or so F&R. No more than 1.1" Have some suspension travel.
Stiffer springs in F then R.
Good Valving dampeners with matched springs. I like this slightly stiffer, perhaps 350# F and 400#R linear and dynoed, within 5% matched. My choice is AST. Had Ohlins on other cars and they are good but no tested on my Mini.
I set the AST dampeners around medium (6) F&R in the beginning of the day and at most I am one or two clicks up or down. Never near full hard...
Choose good springs. I chose Hyperco.

After some bad expreiences with Mini and Mini vendor parts, I started to get "race" level or tested parts only. Stuff breaks at the track and consumer street quality stuff just don't stand up to extended track use. You can eventually weaken suspension fasteners and parts to sheer off and potentially cause crashes. For trackies, never be too cheap.
Corner Balancing is good for the die-hard track addict.
Stiffened chasis with Underbody Struts like M7 to stop body flex

The "stock" Mini provides a very good learners platform up to the beginning advance level. After that, it requires lots and lots of work and even with that level of work, this well prepped Mini might not be able to keep up with a good driver in a well prepped e36/e46 M3. It behaves quite well up to near the limits and if you push it, it can be a difficult handler.

These are just opinions of a Mini Track Junky and they may differ from yours.

 

Hey Purie, I'm thinking about giving local (The OC) autoX a try with my base model '12 MC in the H-Stock class. So far I picked up a set of 15" Holies to mount some Kuhmo XS's on to get started (not going R-Comp until I learn the ropes) and a K&N insert to breath freely. My first real change to the car is going to be a rear anti-sway bar, thus my post here.

The light hollow Hotchkis 22810R is top on my list currently. They state it is +226%, +294% & +383% over stock, but I don't know what "stock" rear bar they are comparing to? In fact, I don't even know what mm bars are on my stock base '12 non-S Cooper?

I know I "need" an upgraded rear anti-sway bar to get started (one of the few upgrades allowed in HS). Do you think the Hotchkis 22810R is a good choice for my application?

 

Good question and unfortunately I have no clue. Sorry.

Well said. And thanks for your opinion and info.

Most people have a different idea on what they want from a car and how they get there. I want to stay in D-stock until I can get the funds to upgrade to the next level. So no camber plates and coilovers for a while.

Go for it, it'll be the best $60 spent on your car. I also live in the OC and I'm real close to El Toro where most of the events are. I'm sticking to the same plan as you except I'll be in D-stock, but our allowed modifications are the same. I recommend getting an alignment done first if you haven't already, are cars tend to come a little out of shape in that department and you might get some good gains from it, it gave me more confidence at the limit. That said, I'd get the swaybar next for sure like your planning.

We actually have the same sized bars since I didn't get the sport package, so it should be a 17mm rear/22.5mm front. I have no clue either about stiffness differences but I'm guess that's the percentage gain over our stock base bar. My reason for going with the 19mm bar was that even in it's softest setting it should be stiffer then what can come on the Mini but I feared that if I went to big I wouldn't be able to tone it down, so I went with the more conservative way.

As far as brand goes, I'd say pick the one that seems best to you. In the end the differences probably wouldn't be noticeable and if you like a particular brand then give them a shot and support their product.

 

I think the Hotchkis rear bar runs about $220 (K&N $45-$60). I'm hearing that it's best to run the lightest setting on the street and push it out to the max for autoX. I'd like to add the JCW Red springs down the road for autoX and to get the 1" drop look for the street, but that's only going to happen when I can do Koni adjustables at the same time ($$$...).

Can you recommend a local place to do the plug removal front camber adjustment and proper autoX alignment, plus install a rear bar while they're at it?

 

I have my eye on some JCW reds as well.

Sure can, muellerized.com

It's where my friends and I go, he even has a ex Mini mechanic that does all the set-ups on the Mini supplied track days. Be warned though, he's expensive. I paid $145 just for alignment, but he's the only guy I trust around here. I've has some really bad experiences, the worst being Stillen, so I don't mind paying more.

 

any starting point recommendations for a street car running in DS other than get as much neg. camber as possible?

 

I recommend tires hands down. It's the only mod that positively effects every aspect of performance and pound for pound is the cheapest to do for how much you get in return.

Try and think if theirs one single mod that can get you better braking, faster acceleration, and higher grip. After that I'd say light weight wheels andI think we can run RPF1's in the stock classes, they meet all the requirements. I can't comment on the rear sway bar being better yet because I haven't done any events with it yet and I don't want to put misleading information.

Here's the rules just in case your wondering and want to shop on your own.

"13.4 WHEELS

Any type wheel may be used provided it complies with the following: it
is the same width and diameter as standard, and as installed (including
wheel spacers if applicable) it does not have an offset more than
+/- 0.25 inch from a standard wheel for the car. The resultant change in
track dimensions is allowed.
Wheel spacers are permitted, provided the resultant combination complies
with the offset requirements of this section. Wheel studs, lug nuts,
and/or bolt length may be changed.
Vehicles equipped with rims having metric specifications may use alternate
rims as determined by using the following procedure:
Diameter: converting the metric measurement to inches and using
the nearest smaller inch diameter rim.
Width: converting the metric measurement to inches and using the
nearest smaller 1/2-inch width rim. Offset and track must still comply
with the requirements of this section."

 

oh sorry - I meant as far as alignment specs go!

 

Ah, no problem.

We actually don't have a choice. For the rear you can adjust the camber and for toe, the shop put 1/16ths toe in so under acceleration the squat will be zero'd out. The front all I got was - 0.7 and zero toe. It'll vary from car to car and I was told setting up the rear toe is just trial and error.

Cheers

 

Here's an update after 2 weeks with TSW springs and an Alta 19mm swaybar set on stiffest.

First impression is less dive and squat, which I liked.

Secondly their is much less rear grip, I need to move the sway bar to softest setting ASAP or replace it with the OEM bar. The car has vicious snap oversteer and I lost control on a mild drift which shot me the other direction and spun out. Before, the car would let me control the rotation with lift of throttle oversteer but now it just snaps into a drift. I do not like, the balance is gone.

My conclusion is that with TSW springs I might not need a stiffer sway bar. But when lowering these cars the rear control arms are a must to get the camber dialed in. I think the more negative rear camber plus the stiffer sway bar is the reason why their is less rear grip. If the balance doesn't return after the control arms installed and the camber and toe dialed I'll remove the springs and sway bar and get some BC coilovers (I may have to retract my no way buy $800 coilovers :P) with custom springs and go from there. My pockets aren't deep enough for Ohlins and I don't know what I can do with my budget.

Cheers

 

Very interesting. I have an H-sport competition rear swaybar and it by no means has snap oversteer. I have never spun the car at an autocross and I push very hard with traction and DSC off. I will be I installing the full JCW suspension and still plan on utilizing the big rear swaybar. The h-sport is equivalent to a 22mm bar and I have it on medium. Will see if I feel differently after the new spring and shocks. But.... The JCW front swaybar is also bigger so that will dial out some of the rear right?

 

I think it might be that the TSW spring rates gain more rate in the rear then the front and with my FSB being the base 22.5mm and jumping from 17mm to 19mm in the rear then on full stiff it just was enough to make the rear to twitchy and let go earlier.

Yeah the JCW FSB is 24mm so the difference might not be as dramatic since your spring rate ratios won't be changing from front to rear.

I still have a lot of tooling to do and will post an update when I get it sorted.

Cheers