I recently picked up a set of H&R street performance coilovers for the Gen2 Mazdaspeed3. H&R states that these will lower the car about 1.2 – 2.5 inches in the front and 0.75 – 2.0 inches in the rear. These coilovers are ride height adjustable via a threaded shock body and feature progressive springs with matched dampers. With the proper tools the install is fairly straightforward, and shouldn’t take more than a few hours.
Everything that came in the box:
- Two Struts
- Two Shocks
- 4 Springs
- Two Wrenches
- Two Adjustable Rear Perches
- 1 Bottle of Boeshield
- Assorted H&R Literature (No Install Instructions)
- This install will be much easier with all four corners of the car off the ground, either on a lift or jack stands. Factory lift and jack stand locations can be found here.
1. Remove the brake line from the strut. To do this remove the clip (using a flat head screwdriver helps). Once the clip is removed push the brake line down and slide it out of the bracket.
2. Remove the 14mm nut from the end link (43-60n*m, 32-44lb*ft).
3. Remove 17mm bolt that holds the strut to the wheel hub (64-74n*m, 48-54lb*ft). A breaker bar makes this easier. Once the bolt is out it’s time to separate the strut and wheel hub. Hit the wheel hub repeatedly with a mallet between the strut body and the brake assembly. This is the most difficult part of the whole process.
4. Break, but do not remove, the 17mm top nut (57-76n*m, 43-56lb*ft).
5. Loosen the 3 adjacent bolts holding the strut to the frame. Be careful, these are the only bolts now holding the strut to the frame.
6. Use a spring compressor to compress springs. Once the spring is compressed it is safe to remove the 17mm from the top of the strut. To do this use an open or box end wrench and an allen key. Be careful when separating the top hat and bump stop assembly from the strut. If it separates ball bearings will go EVERYWHERE! (No Picture)
Front Stock springs vs. new H&R springs:
8. Apply supplied Boeshield to threading on strut body. This will protect the metal from rust and corrosion.
9. Assemble new strut with supplied dust boot and factory top hat. Remember the bump stop is not used with the new strut!
10. Installation is the opposite of removal. To get the strut back into the wheel hub use copious amounts of grease and a floor jack. The best method I found was to lift the wheel hub a few millimeters with the jack and then hit the wheel hub a few times on the side with a mallet. This used the struts own spring resistance to push the strut further into the hub. Repeat this process until you can slide the bolt back in.
Rear Shock Install:
1. Remove 12mm nuts from upper mount. Having a deep socket makes this much easier (22-28n*m, 17-20lb*ft).
2. Remove the 17mm bolt connecting shock to wheel hub (79-105n*m, 59-77lb*ft).
3. Remove the shock from the car.
4. Disassemble the shock. To do this you need a 13mm open or box ended wrench and some way to solidly secure the end of the piston. I used a pair of vice grips, as seen in the picture below.
Rear stock shock vs. new H&R shock:
5. Installation is the reverse of dis-assembly.
Rear Spring Install:
1. Remove 17mm nut from both rear sway bar links (44-60n*m, 33-44lb*ft). This must be done on both sides of the car. Once both bolts are removed rotate the sway bar down and out of the way.
2. Place a floor jack under the rear lower control arm and raise the jack until it makes contact with the control arm. Once the jack is in place remove the 17mm bolt holding the rear lower control arm to the wheel hub (76-102n*m, 57-75lb*ft). Make sure the jack is in place and solid before removing the bolt because once the bolt is removed the springs pressure will cause the lower control arm to pop straight down.
3. Once the bolt is out remove the jack. Now the control arm will freely swing down out of the way and you can remove the spring. Set the spring aside as well as the top rubber mount. You will not be reusing any of it.
Rear stock spring vs. new H&R spring:
4. Before installing new spring and upper perch supplied by H&R make sure you apply boeshield to threads on upper perch. Now install the upper perch so that the recess in the perch (seen in the picture below) lines up with the small weld in the cars frame where the perch sits. This prevents the perch from rotating in it’s seat.
5. Now seat the spring into the lower control arm. If you look down into the spring seat you’ll see a groove that ends with a notch. Rotate the spring in the seat until the end up the spring is seated firmly in this notch.
6. Installation is the reverse of dis-assembly. Use a jack to raise the lower control arm and compress the spring enough to re-install the bolt connecting the arm to the wheel hub. Lining up the control arm and wheel hub can be difficult. Once you’ve got everything all bolted up you’re all done!