Anyone know of an alignment shop in southeast Wisconsin that can corner balance? Tried google, nothing but frustration. I can make a trip down to Chicago if need be, I know a place there, but it would be so nice to find a good alignment shop more local (Fond du Lac)....

 

What's your reason for doing a corner balance? Not something I'd really recommend on a car that is not strictly, or very near strictly a race/tracking day car.
Just ride height the Mini and you will be fine. Don't waste that $100 plus on a corner balance yet.

 

Greg, what ride height would you recommend (and where would you measure from), and on what tire (I'm on 225/45/15')? I still have the stock endlinks on the sway bars; was thinking about swapping those out for something more track friendly. I still drive the car whenever I can when the weather is nice; its indoors for the winter, and otherwise is my toy.

For reference, Marc has the KW V2's, same as I do, and on his R888's he's measuring 3.0/3.5 inches front/rear measured from the jack points (you already know that since you did it!). Mike (TSW) is set up with a one inch difference measured at the arch from front to rear, roughly 22.5 in the front, 23.5 rear on 225/45/15 Nitto's--same tire I have (I tried keeping the rear an inch higher than the fronts at the arch, that didn't work for me, rear end was way too loose for my skill level)....Anyway, there is no way I can get that low (either with Marc or Mikes settings), I don't know if he's got shorter springs, but I don't think it's physically possible to get to those settings with what I have on there now. I do have the HR camber plates up front, I think those add like a quarter inch or so...

I'm just trying to get it setup as best as I can with what I've got--right now it's not bad, the car felt pretty darned good at Blackhawk saturday, but I'm getting a bit of instability at threshold braking on a certain corner--I really need to walk those corners and see if the track is uneven there. Right now ride height is back to where I started from, and camber is at -2.5 front (0 toe), -1.5 rear 1/16 (toe in). I'm just looking for a solid setup where ride height is reasonable and can be left alone; it's probably close now...

 

this paragraph EXACTLY described my car in its former street/track configuration. i have the same alignment specs, exactly. i have the same instability under threshold braking. it's not the track. like you, i felt like i was pretty quick, but something was not quite right.

onasled has the answer for a track car, i believe.

i'll let you know how it works for me, but it will be a while. the shell is on a rotisserie right now.

greg

 

Check out SCCA's and NASA's web site and forums to get input from the racers. When looking for info of this nature, I also find it helpful to find the local shops that the BMW racers go to. Not the posers with the big rims but the racer dudes

That said, instability under threshold braking is probably not due to corner weighting. If you feel it in the steering wheel, I'd hypothesize that its the lower front control arm bushings flexing when loaded up and doing screwy things with the front wheel alignment. At least that is kind of clue has led me those bushings on other cars in my former stable...

 

i agree that the instability under threshold braking is not due to corner weighting or the lack thereof. i added Alta PSRS in an attempt to solve/remedy the problem. it was better, but not gone. i started a thread about this phenomenon about two year ago. no conclusive results, but plenty of hypothesis. i tried almost everything. i'm sure that i'll solve it on my race build.

 

Marc's car is as low as it is because I also corrected roll center and camber vs. travel geometry in the front. I would not go as low as Marc without making these changes.
I measure ride height from the jack pads as it's much more accurate then doing so at the arches. I couldn't even tell what a real ride height would be from an arch measurement. So, is it really only an inch difference from front to back, or possibly more?
So, try and get an accurate measurement from your jack pads. I would not recommend anything more then .5" increase in height at the rear.

So many things can be causing your trail braking "instability". Just hard to pinpoint it without knowing your car better. But for now, I'd recommend checking ride height, getting rear toe to 0 and front to maybe 1/16" out, and getting front camber back to -2 degrees, rear looks OK.

Make yourself a wood wedge like below to check ride at the pads.

 

Thanks Greg, I'll start with that.

 

I might disagree about corner weight being the cause for this instability. Really, corner weight in a full dressed street "Mini" is so close to perfect that not corner balancing it would have little to no negative effect on handling.
Now, ... I do now see that you have a lowered car with adjustable coilovers and NO adjustable drop links? Not real good as you may be pre-loading your sway bars.
Anyway, the problem is this, most of the time. It's that most here just throw on coilovers and do little else. Not making accusations here about anyone, but skipping the hours of setup that I do to customers cars would be like putting on new wheels and tires without balancing and inflating the tires properly.
Just kinda need to start over from the beginning to really find the issue.

 

I just found a place (actually Nate pointed it out) that I think can help get it sorted out locally. The car is actually much better/quicker than it was on the JCW suspension, but it's not where it should be--and I'm admittedly learning as I go along. I'll start with this and go from there. Or you could just move to the midwest....

 

Can you please explain to us why is it bad to preload the sway bars and how can we understand if they are preload? I am asking that because most of us, and you are right, we do not do much apart from getting adjustable coilovers because we do not know what else should we do.

Thank you.