Passengers in the GeorgeCo MINI often complain that they are just but one pothole away from losing a filling. With the stiffer lowering springs and beefy swaybars fore and aft, the effective spring rate was probably in the neighborhood of 450 lbs. By way of comparison, the stock spring rate is somewhere around 200-220 lbs. A stiffly sprung car is great for a smooth racetrack, but can be torture on the street. Having spent a few days at the track in the Porsche with a completely stock suspension, I have come to the conclusion that the MINI doesn’t need to be so stiff. (Remember the early posts about this car when I said I wasn’t going to turn it into a track car. Well, wrong…)
After some additional critical reflection I thought I could achieve 3 objectives by designing a suspension with more compliance: 1.) Improve the ride as measured by the right-seat passenger dyno; 2.) Keep the modifications that correct the glaring deficiencies of the geometry (under-steer and lack of front camber); and 3.) Be cost-neutral. It turns out, there was an unexpected bonus as well: reducing un-sprung weight.
First a recap. Starting with a Stock 2006 Cooper S:
Make the following modifications: Bavarian Autosport Performance Lowering Springs (2″+ drop); Bilstein Sport Struts/Shocks; Eibach adjustable camber plates; JCW Sport Brake Kit; Madness Lower Brace; Powerflex Control Arm Bushings; H&R 27mm Front Swaybar; Alta adjustable endlinks front and rear; Alta 22mm 3-way adjustable swaybar; and HR Sport Camber Arms. The result:
Slammed, stiff, and neutral. No hint of under-steer. Even front tire wear. About 3.5 inches of ground clearance (problematic). Harsh under rapid compression of suspension (pothole). Wonderful at the track. Not so much fun on the freeway. All of the modifications except the front swaybar are quite conventional. The stiff front swaybar really transforms the way the car turns-in under heavy braking, but at a cost. If the front end isn’t loaded, steering became somewhat vague. Definitely not to everyone’s taste.
I decided to keep the bits I liked, sell off the rest, and use the money to buy anything that I didn’t reuse from stock. Gone were the BavAuto springs, replaced by H&R Sport Springs. I Swapped the front swaybar back for stock and got a screaming deal on a 19mm rear bar to better balance the front. I Sold the adjustable endlinks since they aren’t needed with the H&R Springs (the drop is only 1.25 to 1.5 inches so the links don’t really need to be shortened.) Gone was the Madness bar. JCW brakes were replaced by stock along with new stock rotors. I kept the Powerflex bushings and Bilstein struts, but swapped the Eibach adjustable plates for Ireland Engineering fixed camber plates. What I lost in adjustability I more than made up for in comfort. I broke even on cost and shed 26.5 lbs in weight (21 lbs unsprung) and all but 1.5 from the front.) Ride height is somewhere between the two extremes:
So if you superimpose them over each other, you get:
