Suspension Brakes 1st Gen Most liked posts in thread: Are helper springs necessary?

"If" you can get the car back to him then have him do the following (by the way, I truly don't want to sound like a jackass, but I would take the car to someone else or just do it yourself on the most level floor you can find as even you doing it this way wil end up a lot better then what this guy did).

DISCONNECT one droplink on each swaybar!!! And leave it like this until finished.
NEVER use a swaybar to adjust the balance of the car!!! The swaybars must be kept at ZERO preload on a level surface. On ALL road race cars (Yes, even BMWs)

Ride height the car.
Start with the front and set ride height so that front lower control arm is parallel to the ground, or slightly pointing down (maybe 1-2 degrees) from chassis to wheel is even better. I'm sorry, but I'm spaced out on where that brings you in inches when you measure from the ground to the front jacking point, but somewhere around 3" I think. When setting ride height this is what you are doing, setting up correct geometry for suspension design. Hence starting with front lower control arm as it is the most critical component here. Then just set the rear to about the same as the front, maybe .5" higher if needed. This is a good starting point.

Set camber and toe.
Your goals here are pretty much what you set them to already, but MUST be corrected now that the ride height was corrected. My only concern here is that maybe put 1/16 -1/8" toe out back into the front. Zero is ok, but not where I would start if I were you. Camber, ..If you go with 2.5 in the front then maybe go with 1,8 in the rear. Not sure what tires you are using as this does make a difference.

Corner balance the car.
It sounds like you are not there when they corner balance the car? If not did they ask your weight? Your weight must be in the driver seat )with a small percentage on the driver seat floor) to balance the car correctly.
The Mini is a well balanced car out of the box. Think of corner balancing this way. NOT that you need to make the front as close to the rear, but as a four legged table that must have all legs the same length so it does not rock or wobble. He need to get side to side weigth as close as he can, but most importantly he needs to get the LF+ RR equal to the RF+ LR. Corner balancing should take not less then an hour to do, as much as two hours depending how far off he took it out of balance the first time.

NOW.... reconnect the swaybar drop links and set them to ZERO preload .

 

*Smacking inside of forearm like a junky* Yeah... I know what you mean. I've been jonesing pretty bad for a track day. :frown5:

 

Glad things went well at the Glen. Hey, it's a tough tough track to dial in and takes many many track days to do so.
Joe was somewhat correct about his statements, but not fully. What you described is known as throttle steer and is how most front wheel cars behave, though I do think that the Mini is the best balanced FWD car out there. But fact is that you certainly CAN throttle steer a RWD car, it just takes a bit of a softer touch. Do know that the more you do to the Mini to make it stiffer on the track, the more oversteer you will get. You just learn to use it.
Hey, BMWCCA track days are the bast out there as far as I am concerned, and their race schools are even better!. They do it right and somehow keep a great atmosphere that makes to that much more fun. They really teach! What you get at the Glen days are quite a few instructors from the Delaware Valley Chapter, and those guys down there can REALLY drive. I would really recomend you do a driving schools day with either the Boston and or the White mountain chapters at New Hampshire. What this teaches you is just how to control the car with throttle steer and to learn when and what to do when the car breaks loose. Very worth it.

 

You can remove the helper spring IMO. Another thing to consider, when you run the bottom perch up high enough so that it compresses the helper spring, you may be apply pressure to the actual spring as well, preloading it.

Food for thought, there are a lot of coilovers out there sold w/o any helper springs..

Also, i believe KW is forced to supply helper springs due to TUV certification or something a long those lines. Heard that once, but truely dont know how accurate it is, or why it effects us in the US.

 

Yea, NO helper springs in the front. Just take them out. Only need them in the rear as there is a lot more droop back there.

 

For what it's worth I have helper springs on the rears, none up front with the KW V2's, no problems.

 

if you are still tight with your et45 wheels, a 5mm spacer isn't really a big deal. although custom hubcentric ring/spacer might be nice, it isn't required. you can use your current rings and just put a 5mm space behind it. i did this with my SSRs.

your camber will help with fender clearance. no need to dremel....the tire will do it for you.

 

I am so jealous, that looks good. See how the car feels--the rear may be a little high. Bet you're going to rock on the track!

 

Yeah, that's low!! One of the problem with slamming these guys too much is the angle of the CV joint gets less than ideal (which if you talked to Ryephile you already know), unless you've altered the suspension to account for that. I haven't, and it does limit how low I feel comfortable dropping it.

I slammed mine too low initially, brought it up a hair, and that's where it handled the best.

The ratios look good; some people go a little lower in the rear than that, but that is close to where I ended up. If the rear is too high, the car will get squirrely under threshold braking, and oversteer can get a little excessive--I actually went to a softer setting on my rear sway bar and it felt just right, but everyone drives differently.

Good luck, let us know how it goes!

 

I'm not sure whomever corner balanced your Mini really understands what he is doing. Sounds like they are trying to change front to rear weights by slamming the front and keeping the rear up. This should absolutely not be done. It's the cross weights and side to side weights that need to be focused on in corner balancing most cars. Not much anyone can do with front to rear.
Below are ratios from the numbers you provided. Unfortunately the car is a bit of a mess. Sorry, don't mean to sound harsh on this. :-(

Ratios from your results These two values should be close to equal
LF / LR 1.609
RF / RR 1.505


Measured Weight Distribution from your results
Front-to-Rear
Front 1733 60.89 %
Rear 1113 39.11 %
Total Weight 2846

Side-to-Side
Left 1443 50.70 %
Right 1403 49.30 %

Diagonal Weight
Left Front / Right Rear 1450
Right Front / Left Rear 1396

 

^ My thoughts.....

 

8 mm of free space between the spring and the top perchs at full droop on the front is no sweat at all. There is never a time when the Mini unloads the front end beyond spring contact. Don't sweat this at all.
Not sure why you are measuring ride height from axle to fender arch. Best place to measure ride heights are either at the jack points or at the outer most part of the subframes. Corner weight should not be altering ride heights. Ride height is part of tuning the handling characteristics of the car and should be set first. Corner balancing can be adjusted to perfection without altering ride height. Takes a LOT of time.
Just to be clear on your drop link statement. One of each the front and rear should be left not attached until EVERYTHING else is adjusted, ride hight, corner balance, etc. Then when all is done and car is still on the scales, the two droplinks should then be attached and adjusted by your fingers so you can FEEL when they are at zero preload. Then you can jack the car up and tighten down the jam nuts. It just sounded like you were trying to wrench the droplinks during corner balancing. (?)