From what I have seen, many, many "race" cars (and race cars, too) have no front swaybars at all and very little of a rear bar, too if any... Those guys/gals did it all with spring rates.

However, said spring rates would be diabolical on the street... even if you only drove your track car to and from the track. If it's a track queen that rides to the track on a trailer then it obviously doesn't matter...

IMHO, a compromise are stiffer spring rates and matching up the swaybars to your system - and having adjustable end-links is a must (IMHO). You can go pretty daggone stiff on the springs and still retain something that will work to get you to and from the track. In this case, the setup I have seen that's awesome also plays very well an OEM or aftermarket front swaybar - depends on what you have in the back...

 

This, I take it, means adjustable dampers are a must?

 

4deg roll for a street/track 2 deg for track..... watch which wheels lift and adjust accordingly...... take two aspirin and call me in the morning if you don't feel better

 

Car looks to be going straight. Hmmm, I'd say a bad corner balancing?
By the look of the camber I might assume that the track was mostly of right hand turns and you all tried to adjust for that?

 

Yes, they would be... Although, I have to say that all the adjustment in the world won't make up for screwing up on spring rates. Neither will swaybars. JMHO, but spring rates are the most critical element, followed by valving of the struts/shocks, and all the other stuff is for optimizing. A good corner balance is a must, along with a good alignment. It's all about building and tuning a matched system that suits your driving style.

I still think that too much adjustment and too many variables are a bad thing for the vast majority of people out there.

 

Bolding added by me.

That's where I am. I know my limitations and like to think I'm pretty honest with myself about them.
As much as PSS9s, etc seem like the better mousetrap I'm thinking I'm more of a FSD kinda guy.

 

This is the only thing I do disagree with, as I've stated once before here on NAM. Driving style should have nothing to do with the correct suspension setup. The Mini has a sweet spot, somewhere, and it should be the goal to set it up as close to that as you can get. The driver then needs to 'learn' how to drive the car with that setup.
Premium setups change only on track and weather conditions, and tire choice. It should not be set up for poor driving habits.

 

While I agree in principal, some pro drivers like their cars looser while others do not for instance... Many club race drivers I have talked with are driving the same suspensions (e.g. Ground Control/AD setups) and yet different spring rates and other components - being equally fast around the track. If they swap cars (and do at times), they report much the same handling as their personal car and post very similar lap times. In other cases, the same people can't stand the setup of their compatriat's car and yet they're equally fast around the course in their own ride... shrug.

When I talk to any local spec racers, their setups can vary wildly, and yet they're all posting very similar times. Even so, they're starting with the same basic components with changes in allowable tolerances to match their driving style.

I agree that the car shouldn't make up for sloppy driving habits - which ultimately means that either the car is more capable than the driver OR the driver hasn't matched the car with their habits. We all have habits, good or bad. It should be up to the driver to match their car's setup. I mean, the ALMS guys setup their cars one way and 2-3 drivers are expected to get in and make it work...

I agree the MINI probably has a sweet spot - and, there are probably more than a few ways to get there. For instance, my current setup (completely NON-adjustable, except for swaybars) is equally as nice as my best bud's setup (which is fully adjustable). The cars handle almost exactly the same, with the same predictability... except mine has slightly crisper turn-in. The difference in turn-in might be a function of the Cooper versus the S and corner weights, but we haven't nailed that down yet.

Consequently, the variable in lap times we have seen between the cars is a function of the power of his car versus mine, which persists as a consistant gap in lap times from course-to-course (right at 2 seconds on long courses, about 1 second on shorter courses). Cornering speeds are roughly the same, as are G's, but speed in the straights is markedly different... In the very near future, we'll be running the same coilover setup, so we'll see what data we get at that point...

One thing that should prove interesting is dialing my car back in once I go to coilovers... I expect the new setup should get me a bit closer to his times, but I expect once it's dialed in and baselined that we'll see the same consistency in gaps...

 

IMHO unless you are going to have a trailered dedicated track MINI then you need adjustability - are linear springs better for the track - probably - but progressive springs with single or double adjustable shocks are probably the ticket for a dual use MINI. I'm low on theory and high on going out and trying things. if I have a theory it would be that lower spring rates and stiffer sway bars are better than the inverse. I've been to one DE at Summit Point in the MINI and 4 years of autocrossing.

I've tried lots of combinations and the PSS9's are for me the perfect compromise. That doesn't mean Obehave shouldn't get his FSDs. I also have the HSport front bar that I run full soft 95% of the time, but I think I have more front grip with it than without it.

I adjust for rotation and conditions first with the PSS9 shock stiffness, and next with the swaybar stiffness, I tend to keep my tire pressures consistent and not use them to tune rotation in and out. My tire pressure choices are based on trial and error and a good pressure gauge and pyrometer. I like a car with predictable rotation - somewhat looser than neutral. If its too loose I can't handle the slaloms very well.

adjustability is a double edged sword, and you can easily just make things worse. But with a logical and orderly approach and some trial & error you can sort things out.

Honestly I have my alignment specs decided, tire pressures decided, and I haven't even adjusted my shocks much this season - and my front bar is on soft and the rear bar in the middle. It's about learning to drive faster at this point.

BTW great thread

 

Thanks Dave.

What spring rate(s) are you running front and rear?
My main interest in the PSS9s is that I can run smaller diameter springs and this will allow me to pick up a little more - camber without pounding dents in my bodywork(which will never happen ).

Since this is a track related thread you can PM me if you want so we don't go too OT.

 

"I've tried lots of combinations and the PSS9's are for me the perfect compromise. That doesn't mean Obehave shouldn't get his FSDs. I also have the HSport front bar that I run full soft 95% of the time, but I think I have more front grip with it than without it."
FSDs cannot be revalved to run spring rates required at the track; maybe someday, just not now. PSS9s need to be converted to 2 1/2" springs to make them trackable as Hoosiers and Kuhmos both like 3 deg neg camber. There are race setups available for the Mini but you have to know what you are looking for and who to call!

 

I am also interested in trying linear rate springs up front for dual street/autocross purposes. I'd like to maintain the ride height and available suspension travel that I have now, or possibly raise the car a touch more.

So, does anybody know the free length (and other pertinant dimensions) of the PSS9 springs? I'm guessing that the diameter for the fronts would be the same as those already on the rear, but I'm not really in a position to take mine back off the car for measurement purposes

If possible, info on both front and rear would be nice as I'll probably bump the rates up a touch. I'd like to maintain approximately the same balance front to rear. The car feels pretty decent once it takes a set in sweepers. I'm just trying to get transient response back.

I suppose I'll also have to buy a different set of camber plates for the smaller diameter srings too.

Thanks in advance.
Scott
90SM

 

Just to continue this interesting thread....

There has been some mention of massively stiff springs and how, somewhat, unnecessary anti roll bars are.
A couple questions come to mind;

Are we talking about a MINI or a car with a much lower CG? Stock ride height or lowered? Both can make a big difference in roll center height which very much effects the need to control roll. An F1 car for instance doesn't have much of an issue with roll. A MINI at stock or even 1" lowered will.

If super stiff springs are the answer then extend that thinking just put in a solid bar and make the car a Kart.
That isn't logical. Over stiff springs reduce compliance in the unsprung mass.

Don't you want springs to be ?;
1. at a nominal state at the preferred ride height
2. be strong enough to avoid solid stacking/ bind under maximum load but little or no more stiff than needed to meet these conditions.


Adjusting an anti roll bar won't impact corner weighting and can make track adjustments simpler. Swapping springs per track or altering ride height is more involved.

Discuss

 

Actually, adjusting a swaybar DOES affect corner weights and IMHO, it's something everyone forgets. With the stock fixed length swaybar endlinks, you're going to have preload on the swaybars no matter what you do and that will affect corner weights. You'll end up dialing that out with the ride height adjustment, and you'll still have preload on the swaybars...

With ballast in the car and using adjustable endlinks, we saw a change on a very well corner balanced car... between neutral and just one full adjustment turn of the adjustable endlinks on the scales, cross-weights did change.

Also, I will say that dialing out all swaybar preload made a rather major difference in what I already thought was stellar suspension performance... It got even sweeter.

I'm about to go coilovers, linear rates all around... I plan on disconnecting both swaybars and leaving them disconnected for the initial corner weighting. Then, connecting the swaybars and adjusting the endlinks to ensure there's no preload on the bars and that I haven't messed with my corner weighting...

 

Could you explain how this preload condition exists?

 

Swaybars are bolted to the subframe in the front and the rear subframe in the back. In the front, the swaybar's connected to the strut tower via fixed length endlinks. In the rear, the swaybar's connected to the bottom of the rear trailing arm. Now, sit in the car - you've added your weight to the driver's side and changed the corner weights. Since the endlinks are fixed length and you've compressed the suspension slightly on the driver's side, you've added preload to the swaybars (they're slightly twisted, in other words).

 

That's what I was thinking. There's a torsional load applied by something, driver(big load in my case ) , fuel, etc.

I have considered these in the past but couldn't justify the expense on what is basically a stock suspension. I do have the ubiquitous anti roll bar upgrade and now front camber plates.

You've now given me an excuse to spend more money on my car

 

.... if you have one wheel higher then the other then the swaybar is twisting. That is preload. To remove preload, which is a MUST for maximum handling, you add the adjustable droplinks. Now you can remove that swaybar twist with either shortening or lengthening one of the two droplinks.

Yes, corner balancing should always be done with the disconcertion of one droplink per bar. Once balanced, the car should not be moved and the driver weight must remain in the seat until all drop links are reconnected and adjusted for ZERO preload.

Yikes... my internet is S L O W today. So this post came up late. See you already have this at hand..

 

The difference is quite marked, IMHO. My car turns in better in both directions now and you can feel the bars loading more progressively. I also feel the car is more predictable. I also notice less lifting of inside rear wheels under trail braking into corners, and less wheelspin from tight corner exits. To me, it was like taking the suspension to yet another level...

 

Off to spend money...........

Thanks to both of you

 

Spending money on the MINI is fun! Well, I think so anyway - the wifey doesn't think it's as fun as I do...

 

I have found this site to be an interesting "Cliff Notes" on handling - not as thorough as the Puhn and Smith books but not bad.

 

I too have been wanting to try linear spings on the PSS9's, but was unable to get any good, solid info to proceed. I just know that a guy at H-Sport added Hypercoils to his fronts, and he really likes them. I met him at the Monterey Historics last month, got his biz card, and somehow left my MINI baseball cap in Monterey, with the dang card in it...

https://www.northamericanmotoring.co...3&postcount=20

For fun, some should try disco'ing a sway bar link and see what changes...

 

Tony,

Key restrictions - if you wish to retain upper and lower perches - is spring diameter and length. Beyond this suggestion I know nothing about the PSS9s.

Happy hunting

 

The guys at Hypercoil are very responsive.....

I saw a piece on "Speed" where they were saying the trend is to set the car up to make it as fast as possible for the track/conditions and make the driver adapt rather than set the car up for the drivers "requests"

PSS9s softer in front....front sway bar soft... rear sway bar middle... feels good to me as well.... what tire pressures etc (if that is not a competitive secret)