So I am prepping for the coming autocross season and decided to build to SCCA D-Stock rules (even though I mostly autocross with the BMW club).

I had to decide what suspension to go with. Specifically, I decided to use the Factory (dealer installed) JCW suspension. But, with D-Stock, I can replace one sway bar and the shocks. So, I ordered JCW springs and the front JCW sway bar. The rear bar, by the way, is a Hotchkiss H-sport Comp bar.


When ordering springs, you have to work directly with a MINI parts person (or someone who knows) because there are four different part numbers depending on if you have a manual or automatic transmission and if you have a sunroof or not.

Anyway, changing the front sway bar was a BEAR (6 hours work by two guys with a lift)! I would strongly recommend against it unless you *really* hate body roll and you have to because of the rules you are working towards (for example SCCA D-Stock). The rear bar was pretty easy (only 3 hours solo).

The big question was what shocks/dampers to use. At the extreme high end was Truechoice Double Adjustable Koni Sport shocks. At the low end was factory JCW shocks. In my price range, it was going to be either Koni Sport (single adjustable) or Koni Frequency Selective Dampers (FSD).

I did a lot of reading and research and found that Per Schroder of Grass Roots Motorsports ran them on a Gen 1 MINI with great success. Basically the low frequency behavior is similar to the lower settings on the Koni Sports and the high frequency behavior takes the edge off track irregularities - thus keeping the wheels on the ground for better traction. Also, Tire Rack did a comparison using E46 BMWs with sport springs, and either stock shocks, Koni Sports (softest settings), or Koni FSDs. The FSDs rode best and returned the best autocross times.

So, Koni FSDs it was. I know I could have probably squeezed a bit more performance out of the Koni Sports with a lot of testing and tuning, but, I don't have the time to be a research driver. Also, the car is a daily driver and the soft behavior of the FSDs on road bumps was appealing.

So, Four hours of wrenching later I have my suspension fully installed.

I haven't really driven it aggressively, so, I can't comment on performance driving really. I have done donuts in a wet parking lot and it seems fairly responsive and balanced. What is hugely impressive is how it handles road irregularities. For comparison, the previous suspension was the base Cooper S suspension. The car is smoother in all circumstances - I won't say it erases the bumps and such, but, it really, really smooths it out compared to the factory system.

I will report back in March after the first autocross of the season.

Bob

 

FYI you are NOT suppose to use ANY lowering springs with the Koni FSD's.

We have tried it even with the slight lowering of the JCW springs and the FSD's ended up leaking a couple months later.

I would have suggested going with the Yellows as they could be built into double adjustables later.

 

This is right from there website.

 

I will keep an eye on them and report my experiences back to the community.

Bob

 

The Koni FSD blanket statement doesn't apply to Mini fitments. If you click on your application on Koni's website it echoes what Way said.

However, I have Koni FSDs W/JCW springs and seem to be making it work. I trimmed the bumpstops up front. I also made my own rear spring pearch & shock mounts in the back after triming the bumpstops. I gained an inch of suspension travel in the rear with these modifications.

I tried Way's bumpstops & found them to be way to hard with almost not compression.

Wish I would of found these bumpstops before finishing the project since they make a stop specifically for FSDs on Minis:

http://www.fatcatmotorsports.com/FCM_Products_Mini.htm

 

I cut a half inch from each bump stop.

Bob

 

To echo what Way said, I received this email directly from KONI:

"Our KONI FSD shock absorbers combined with any kind of lowering springs on the 1st generation New Mini is not the most fortunate combination. Available stroke on the shocks absorbers is limited, even more so with lowering springs fitted. As a result we feel the bump rubbers come into play too soon, to which the self-adjusting FSD shocks respond. The overall ride is an improvement over stock without a doubt, but under certain circumstances we feel the potential of the KONI FSD’s is not fully used. FSD’s combined with original length springs will not have this issue.

In case you want to remain the ride height with your current JCW springs I want to suggest to pair these with our KONI Sport shocks, which have the valving to match and still provide both handling and comfort improvements over stock."

 

Like others said the FSD's will work on some cars with lowering springs, but the MINI FSD is not one that can be used with lowering springs.

 

^+1

 

Folks,

I knew what the Koni web page said. I also did a lot of research on this and other MINI enthusiast web sites. I agree that it is a risk operating these shocks 10mm outside of their approved range. However, I am taking that risk. I am posting this in case anyone else out there is contemplating FSDs, or FSDs and JCW springs.

As I said, I will update this thread from time to time to indicate how well the shocks are doing. I will be sure to keep an eye out for leaking and if I experience any, I will duly report it and probably switch to Koni Sports.

Bob

 

Why? With other shocks out there why risk it? Money to burn?

 

1) There are no other shocks out there that do what FSDs do, so, it is worth the risk.

My car is a daily driver (60 miles round trip), I need to consider the compromise between comfort and handling. I have read that Ohlins makes a great coilover that is a perfect compromise between ride and handling. But, they are more than twice what I have paid and kick me out of D-Stock.

2) There are several others on this and other forums that *have* run this setup for a long time (at least one that I found with over 30k miles on the setup) that have not experienced problems.

3) I could not find more than three people that actually *did* report issues with this setup. It is onlly a 10mm drop, whereas most "lowering springs" are between 25 and 50 mm drop.

4) One of the problems I have read with running FSDs with lowering springs is that they hit the bump stops too frequently and the abrupt stop is not so good. I have trimmed the bump stops to reduce the frequency of bottoming out.

So, in answer to your question, why take the risk? The risk appears to be relatively low, the shocks fit my mission better than anything else at anything close to my price point, the shocks allow me to run in my chosen autocross class, and I am able to mitigate at least one of the failure modes identified.

I hope that helps you understand my position.

Bob

 

You sound like my kids as they have all the answers too. I like your attitude as you are doing what you want. Kind of like Burger King, you paid so you are having it your way. Keep us all posted.

 

PhD in engineering plus 15 years of risk management and failure analysis. I am not the guy with all the answers, but, I play one on TV.

I will keep everyone posted on my experiences. I can't wait until the first autocross this March.

Bob

 

What setting are you going to run your H-sport rear bar on? Last year I ran mine on medium. This year I have the JCW suspension but have yet to install the front swaybar. I need to get that installed. Anyways I am thinking of sticking with medium again this year as it seemed to work really well. If I feel more understeer after the first event then I will consider full stiff I guess.

 

I haven't autocrossed it yet, so no opinion. I have been driving it with full soft so far. On one slick morning, the rear slid on me on a cloverleaf. The electronic nanny took care of me though.

With respect to the front bar, I wouldn't bother unless you need to fit in a particular race class - like d-stock. It takes six hours at least. I had a friend helping and a lift and it took six hours!

Bob

 

How much do the jcw springs Cost? I'm considering just the jcw springs with use on my factory installs sports suspension but if they are ridiculously priced may just do the comp rear sway bar from hotchkis this year.

 

I think really the only reason I would put the JCW springs on would be if I was doing the entire suspension to stay in an stock Autocross class. Other than that I would get some other springs. However if you are not after much of a drop like I was then the JCW springs make sense. I put the entire suspension for D-stock. I think just the springs cost me $380 plus shipping. That price puts you in the range of Swift springs which people say are some of the best around to get...

 

Good point khd. I want to improve handling while staying stock but am not in the financial position to do full suspension swap.

So I'm between the bigger rear sway, koni sports or jcw springs. I need to decide which is the best bang for the buck for this season.

 

There are lots of guys here that will suggest that your first mod should be the RSB. The nice thing about that change is that the aftermarket ones are adjustable, so you can find a setting that suits you. Then if you change springs/dampers at a later date you can re-adjust the rear bar, if required, to meet your new suspension components.

Mike

 

It was my first mod. Then 6 months later the rest of the JCW suspension less the JCW rear swaybar since I already ad the H-sport Competition bar.

 

Is the h sport comp bar the 25mm hollow (22mm solid equivalent) bar the best option in terms of autox use while maintaining street use? With the OEM sport suspension with a 18mm OEM bar I guess this h sport is really the only logical upgrade choice. Thanks all for the replies. This is a very informative thread.

 

I was worried that the big sway bar would ruin the ride, but, it didn't. I hardly notice it at all on daily driving. I do notice it when I pull into a driveway crooked at very low speeds.

Bob

 

When pulling in driveways You can get a rear tire off the ground at certain angles with the stiff bar!

 

I am pretty sure that is what is happening!