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Stealth Ready for Shakedown
With more than 24 hours to spare, I finally finished the F-22 for the first track outing of the year. Since I was running out of time, I had Dan Martin’s shop finish the front suspension and fix the cam gear seal.
I’m really impressed with the Bavauto springs. The ride height is aggressive but not slammed. The ride is firmer but not harsh. I’m looking forward to getting it on the track and seeing if I still need to upgrade the sway bars. Compare the ride height to the 20 year-old stock set-up.
I also had them install the IE front strut bar as well. The bar looks really slick in basic black.
Now all I need are some go-fast stickers…
Stealth Springs into Spring
Thanks to the break in weather, I was able to start the suspension work this past weekend. The photo above shows the difference in size between the stock rear spring and the Bavauto spring.
Shorter springs require shorter shocks. This photo shows a comparison of the Bilstein HD shock with the Sport Shock.
This photo shows the stock spring prior to removal. Changing springs and shocks on the rear is fairly simple.
- With the car on jackstands, remove the wheels, and support the differential with a floor jack.
- Lower the exhaust by disconnecting the two rear brackets and the rubber hangar. Support the exhaust in the lowered position.
- Remove the bolt from the differential housing that mounts the differential to the subframe. Slowly lower the jack. This will take the pressure off of your axle shafts. You may have to disconnect your speedometer sensor if the wire is too short to drop.
- Remove the nuts that hold the swaybar to the trailing arm. Use another jack to support the trailing arm and disconnect the shock at the base. Disconnect the shock from inside of the trunk, but don’t let it fall. Remove the shock.
- Press down on the trailing arm. If your springs are really worn out, you may be able to remove them by hand. I didn’t have that luck so use a spring compressor to carefully remove them.
- Replace spring pads and reinstall new spring. Jack up the trailing arm a bit to hold it in place.
- Install the shock from inside the trunk. Now is a good time to replace the gasket under the shock mount. Think about adding reinforcing plates or a strut bar at the same time.
- Reattach the lower shock bolt. Tighten all bolts to torque specifications.
- Repeat for other side.
- Raise the differential and reattach bolt. Torque to specification.
- Attach swaybar bolts and wheels. Remember to torque the lugs.
- Attach exhaust hangar and brackets.
The photo above shows the new springs installed. Notice the difference in height by the gap at the top.
I also added the strut bar. I even changed out the brake calipers while I had everything available.
This final picture shows everything put back together with the new RA1s and Konig wheels.
Compare that to the off-roader height from before the change.
The final change was the addition of a new lip spoiler. It’s actually not the right one for this car, but with the lowered ride height and shallower design, it has a better chance of remaining attached after multiple autocross cone-crunches. Notice the ride height in the front. That will come down when the front springs are changed out.
Suspension Tuning
It’s tough finding the right suspension for autocross, track, and daily driving, but I think I have a good mix right now. To recap: Texas Speedwerks springs (stiffer, linear, lower about 20mm); Ireland Engineering Camber Plates (increase front end negative camber); H-Sport rear lower control arms (correct camber in the rear due to lowering); Alta adjustable rear anti-sway-bar (set to medium stiffness); and M7 Strut Tower Reinforcement (STR) Plates to prevent mushrooming.
I did my first autocross of the year and first event with a new club, the Capital Driving Club, this past weekend. Once the course dried out, the car handled quite well. I was probably the fastest car on street tires and maybe in the top 5 of 24 for the Sunday test & tune. The car is very neutral. I’m still suffering wheel-spin due to my lack of a limited-slip differential, but I think the car is dialed-in pretty well. Now it’s up to me to raise my skills to match the car.
MINI Rear Lower Camber Arms DIY
Notwithstanding the six inches of snow and ice in my backyard, it’s almost track season again. My first test & tune autocross is less than two weeks away and on March 17th I head off to the main circuit at Summit Point for the first HPDE of the year. My current project is to improve the suspension of the MINI. My goals are to fine tune the front end grip by installing adjustable camber plates in the front; install some firmer springs that will lower the car just a little; and install adjustable lower control arms to keep the rear camber in check. I don’t think I’ll get to the plates and springs before my next track event, but here’s how to install the control arms. This information is posted for entertainment purposes only — no wagering. Attempt at your own risk.
In this post, I’m installing Hotchkis Sport adjustable camber arms on a 2004 Cooper S. They are quite a bit beefier than the stock arms and the design is quiet (unlike heim-joint arms). The 2002-2004 cars did not have any rear camber adjustment built into the rear wheel carrier. On the 2005-2006 models there was a limited amount of adjustability, but not enough to compensate for lowering springs. If you install performance lowering springs, it’s critical to use camber arms to correct camber or you will wear the inside edge of your tires and possibly rub the inside wheel well. The instructions below came from Hotchkis Performance, with my two cents thrown in as well.
Tools Required:
- 18mm wrench
- 18mm socket
- one inch extension
- 1 1/8 inch wrench
Raise the rear end of your MINI and place it on Jackstands. Be sure to work on a level surface and only use the official jack points.
With the vehicle slightly off the ground, you can start on either side of the car. You do not need to remove the road wheel. Start by removing the lower link. Use the 18mm wrench to remove the outside bolt. [Spray it with WD-40 first. On my car one side was quite corroded.] As you start to remove the bolt, the wheel will want to come in as the hub is only supported from the upper control arm at this point. You may need to use a jack to push up on the end of the lower control arm to relieve the pressure to remove the bolt.
Use the 18mm wrench with 18mm socket to remove the inside bolt. Depending on the length of your socket, you may need to use the extension. There isn’t a lot of room to get your socket and driver in between the sub-frame and foot-well. I had to use my breaker bar since it had a lower profile than my driver. You may have to push back the aluminum insulation to free the inside bolt. Once the inside bolt is removed, the arm will drop free.
Remove the control arm and place it on a flat surface. Place one of the new control arms over it and line up the sleeves at one end. Adjust the new control arm so it is the same length as the stock arm. Use the 1 1/8 inch wrench to tighten the jamb nuts. Use the supplied grease pack to grease the exposed bushing surface on each arm before installation.
Install the H-sport arm with the longer section mounted to the inboard side and the short section at the outboard side. Slide the arm into the inboard mount first before the outboard side. Make sure the grease fittings are pointed down. If you car is off the ground, you will need to push out on the bottom of the tire from under the car to have enough room to push the bottom of the arm in place.
Secure all hardware and repeat the process for the opposite side. The Bentley manual lists the torque on the control arms as 74 ft. lbs.
Expected time is 1 hour. My time: more than that. [More like 2 hours for the first side and 30 minutes for the second side.]
