these RSS club sport use bilstein shocks up front with a very high compression rate. i did not have any proper equipment to measure them but with most of my weight (170lbs) on them pushing as hard as i could onto the bottom with the other end on a 2x4 on the ground, they would move about 1/2 to 3/4 inch a second. by contrast, the stockers on mine (which were the stiffer ones with the thicker oil (early 2003)) i could compress completely in about 3 seconds.

that being said, using the stock springs would limit how stiff you could go with the shocks, but i'm pretty sure you know that already. also, like satay said, doing this with stock springs will induce a LOT of lean...

and it's absolutely not off topic! i started riding the tangent mobile as i typically do , but this thread is mainly for front swaybar opinions/personal experience with or without/innovative ideas.

 

I'll add this comment...take one very well thought out set-up - sans dampers - and apply it to three different cars - ride height, spring and bar rates, tires, brakes etc. Now, add three completely different dampers to each. Each will more than likely perform in very different ways. Each may posses the same damping force, bvut have a completely different damping velocity curve.

Dampers are incredibly important and have a way of really complicating setups...just because I went the budget route... ...

 

satay-ayam: With the Leda double adjustable shocks, I can crank the compression way up. It's almost like having stiffer springs.

My "theory" on front tire wear is that if you get the car to rotate (via alignment, high rear shock settings, high rear tires pressure, etc...) then front tire shoulder wear isn't a problem. My race tires have worn surprisingly flat with -0.2 camber and the 22.5 mm front bar.

But yeah, NO front bar would probably be too much in my case.

 

Meb / Chris: These dampers are digressive. That means they have very heavy low speed damping (platform control) and lighter high speed dampening (rough road bumps). I'm really surprised at how much a set of good shocks can control chassis lean/pitch. But yeah, in the middle of a big sweeper, the shocks are worthless. But I'm hoping with a soft front bar and proper rear toe setting, the car will be balanced enough that I won't be grinding the outside front tire. (well see!)

Unfortunately one of the front canisters is leaking, and with Leda going bankrupt I need to send it to Racers Edge ASAP before they run out of parts to fix it. So I'm going to have to run the stock front shocks for the next event. :(

 

Mitchman,

Regarding your fast sweeper comment...dampers control the rate of lean (as you know). So in fast transitional situations, I'm not surprised the dampers you have work very well. But in fast sweepers, they eventually find themselves in the same place all dampers do. So spring rate/bar rate balance help here.

On ther other hand, if your rig is fast and stable in, and fast out - you can put the hammer down in the last third of a turn - I don't think you're in a bad place. It's a tuff balancing act with a front driver but the radius of the turn determine everything...well, so do other drivers

 

Very well said. I agree exactly.

I've ran our car 4 times this year and in all 4 cases the courses had a bunch of 180 degree sweepers. But in 2 weeks we're running on a different site that is mostly transistions with maybe 1 or 2 sweepers. I'm really bummed that I have to run my stock front shocks as I'm sending off my Leda front shocks for repair. :(

 

don't hurt yourself. Don, dhm, indicated that Leda may be transfering ownership and or debt??? Don is under the impression that Leda is still available...

 

Very interesting thread and had to jump in with my 2 cents.

I have the HSport front and rear bars -- front is set on soft rear on middle. I also have PSS9's that come with stiffer than stock springs but not excessively stiff like some I've tried. Been autoxing it since late 2002 and have moved my classes from STX-> DSP -> SM as I have modded the car.

I agree with meb that there are multiple variables at work here - but to generalize there are two camps -- softer springs and stiffer swaybars on one side and the stiffer springs and softer/no sway bars on the other. Dampers and camber etc play into the equation as well but as a generalization I think this works.

The setups with much stiffer springs likely don't need to stiffen the front bar and handling would suffer as a result

I have a Quaife so am less prone to the wheel spin on corner exit (another variable - LSD or no LSD). I have also found thru trial and error that PSS9s adjusted to the softer side works better for my driving style and car. I have had to stiffen up the shocks significantly only on smooth concrete sites. I tried both the front and rear bar on full stiff setting and felt that there was less grip.

David

 

Correct me if im wrong, the thing I really like about this idea is: You can have a really good canyon, street and track set up then unhook the front bar and have a really good auto-x set up.

 

Chris and the rest,

Feedback time on a year old thread. Been chomping at the bit all year, waiting for the chance to try Chris' idea about the front anti-roll bar 'delete' option for the track. Have PM'd both Michael (meb) and Chris (sonichris) over the course of the year for moral support and advice.

Installed 250# springs all the way around, raised the front roll center back to near stock height, disabled one of the front anti-roll bar links, added a couple of extra holes in the stock rear anti-roll bar for roll stiffness adjustment and tested the car on the street. Found the ride 100% better, seemingly neutral handling on wet curves near the house, and the body roll dynamics seemed 'okay' to me. (what ever 'okay' is to me)

Had my first track day of the season yesterday. Wow! I'm never going back! A signiture characteristic of our local circuit is irregular paving and pronounced pavement rippling in portions of the momentum line. You can see where I am headed: potential for big problems with wheel compliance at speed. To make matters even more challanging, the track surface started out flooded and progressed to merely damp over the course of the day. The new MINI front anti-roll bar 'delete' suspension set up ruled, big time. MINI was the quickest car in my run group of 15 cars in the wet morning. I focused on my long distance sight lines and smooth inputs. No problem going relatively fast. I was simply amazed. Like, really amazed becaue I wasn't 'trying' do do anything but stay alive and drive correctly. Lapped the entire run group almost twice each session. In the less wet afternoon conditions, the run group balance tipped back to the normal and expected hierarchy of car performance. In the afternoon, I had the pedal to the metal everywhere as I would in the dry, no tip toeing here. She (MINI) gave all she had to give. The point is, the front end remained planted into and out of corners. Less go-karty. Less understeer but with a compliant front suspension. No lifting of the front inside tire. The signiture ripples resulted in much less lateral rocking motion to the car. Using Toyo R888 'R' compounds at the track.

The front anti-roll bar 'delete' is not a new idea at all, but an approach that can have benefit for the MINI. I see it's major value for slick track surfaces like yesterday's wet conditions or on the irregular track surfaces that characterize our regional circuits; both situations where tire and wheel compliance are issues. Smooth surfaces like Laguna Seca or some of the other well maintained circuits, dry conditions, and/or slicks would call for a more typical MINI high roll stiffness front end set up; one that focuses more on front wheel camber control for a surface where wheel compliance is less of a challange.

I am a happy camper. Thanks Chris.

John Petrich in Seattle

 

that's great! Glad to hear that worked out well.

 

Hi John!

Congrat's on doing so well with the setup on your Mini!

Just wanted to support your findings with my experiences as well. All last season I autocrosses our 2007 Mini Cooper S with the stock suspension, Leda double adjustable shocks AND a customized smaller 22mm front bar from a standard Cooper. Before I installed it I took the bar to a machine shop and had him machine a flat spot in it that ran across the center section of the bar. This effectively softened the spring rate of the bar (same as a smaller front bar which wasn't available).

The setup seemed to work well for me all season. Between the high compression rate in the rear shocks and the softer front sway bar, inside wheel spin on corner exit wasn't a problem. (I could site lots of 1st place victories, top PAX times, blah, blah, blah)

I've always thought that people were crazy to go with a larger front bar on a FWD car. Now if we're talking about RWD cars, then the larger front bar can have some benefits.

 

Mitch,

Sounds like a lot of people are thinking the same thing as you articulated. I call it 'the road less traveled' in terms of MINI suspension set ups. Love your custom front anti-roll bar execution. Using your brain. I was way too lazy to drop the subframe. Just disconnected a link. But, I had the 250# springs also.

How did your autocross season go last year? We just must get together at a road course track. I cannot travel to Spokane in either March or June. But maybe, you could come West or Southwest?

All the best,
John Petrich in Seattle

 

Good to hear from you too John!

I had a great season. I wish I would have done better nationally (3rd place), but around the region I would finish 1st at most of the events I attended. I was able to participate in my first track day with ProFormance a Pacific Raceway back in June. It was a lot of fun (except for the $500 price!). I plan to do it again some day.

This season I've switched to a Mazda MX-5 with the special MS-R option package (Motor Sports-Racing). It's good to get back into a RWD car, but I do miss the power of the Mini. I've put the Mini back to stock so my wife can start using it as her daily driver. But I left the front sway bar and shocks on it so it would be pretty easy to use it for a track day if I can fit it into my busy autocross schedule. I'll try and remember to let you know if I do another track day this season.

 

this is great! i'm glad to hear that it's working for you guys. i'm still no front swaybar and loving it.

 

This chassis tuning chart may answer some of the questions raised as well as show the interaction of various changes...

http://www.rogerkrausracing.com/Tech...verunder.shtml

 

Under the "Understeer Corrections" column, it says, "Remove weight from the front of the vehicle", and, "Add weight to the rear of the vehicle". What's up with that?

Also, I don't always agree with their tire pressure recommendation.

 

That's because front heavy cars typically understeer. Move the weight around to fix that...Notice how many 50/50 weight distribution cars are pretty neutral? Get the weight off the front to reduce plowing (understeer). That's not always possible especially with front engined cars, so other means are used to fix the problem: Tire pressures, sway bars, suspension geometry etc..

On tires, lowering the rear pressures increases slip angles and oversteer. Not sure what you're disaggreeing with..

These rec's have been around for Many, Many years and are pretty basic and the basis for many chassis and Handling books....

 

It just seems if the front end is having grip problems, you would want to add weight to the font. Like lower front tire pressure within a certain range or stiffer rear bar, stiffer springs, stiffer compression damping or just the opposite, soften settings in the front, within a certain range. With all other things being equal.

50/50 weight distrabution isn't the end all to getting a car as neutral as possible.

 

That's fine if you want the car to understeer more.. Lack of grip or plowing is the result of basic understeer.....As the chart illustrates, there are numerous ways to moderate it..

 

Ok, it has been almost another year, and I'm curious to hear if you guys are still minus the front bar; and if you have any new experiences, please do share...

I was out of the country quite a bit in 2008, and I didn't see (or drive) my MINI all that much. It's currently on jack stands now as I finally had the time to address an oil leak. And with the front wheels off, after seeing the end links, I remembered this thread...

I have 350# linear spring up front (on PSS9's), so I'm thinking that lean should be minimal.

I periodically check-out GRM, and found this discussion on spring rates somewhat interesting, and thought I'd share...

http://grassrootsmotorsports.com/for...es/3361/page1/

 

Hey Tony,

Not sure I would remove the front bar with only 350# up front. Also it's a complete rebalancing of the entire car so you will need to do work on the rear also.
Get up to 500# in the front and then "think" about it. Best next step is to order a Mini1 front bar from the UK.
There are so many different ways to approach this. I know some FWD race guys that laugh at anyone that runs anything in the front. I have also seen the top grand am teams bounce back and forth on this. They used to run heavy spring rates and no bar, then heavy bar and light rates, and now I see they may be going heavy bar and hard springs.
I have a pile of springs and a stack of bars for the race car. All depends on weather conditions and track on what works best.

Street driving? I'd keep a front bar for sure. Spend your time on the springs, much more fun and much more gratifying.

 

Thanks Greg. I think I still might just try disco'ing a front link to see how I like it. The loss of traction with power application coming out of turns has always frustated me... I will get an LSD whenever I purchase an '05/'06 tranny, but even then, it would seem that traction can be improved with less or no bar. Playing with spring rates might be fun, but would this help with improved corner exit traction?

I'm going to be lowering the subframe to replace bushings (upon asking, Michael gave me a list of things to do), so I'd like to experiment first. If it proves to be worthwhile, I'd remove the bar, hardware and links at the time...

I've been wondering... If one were to go sans front bar, what if any difference would adding something like the X-brace provide? I'm trying to think of a way to let each wheel/tire do its thing, while still keeping the front portion of the chassis tight or rigid...

Greg, I was going to ask RSR, so I appreciate you sharing what the Grand Am guys have done and are doing.

Chris, John, you guys still liking no bar? I wonder what Alain and Steve run with (or without)?