Today we will be looking at how to build and install coilovers on the front of your E46 BMW and lowering springs and struts on the rear.
Lets start with the fronts first which will look like this when you take them out of the box.
There are three adjustable collars on this particular set of coilovers. The lowest collar allows you to adjust the ride height without altering the overall spring compression and the upper two are there for adjustment of the spring compression. The more the springs are compressed the less travel there will be in the suspension and the more “static” it will be.
I also brought aftermarket top mounts for the front suspension which allow you to easily adjust the camber (lean of the wheel) by loosening four bolts and sliding the coilover up or down a runner.
Some more expensive coilover kits already come with new top mounts but I am a peasant so I had to get them separately.
To install the top mounts remove the bolt at the top of the coilover. Health and safety would advise that you put sring compressors on the springs before removing that bolt but I did it without them and found that the spring wasn’t under that much tension.
Now for the fun part of getting them in the car!
Firstly you will want to remove the top bolt of the drop link holding the anti roll bar to the shock absorber. These are probably the trickiest bit of the entire procedure. Put a 16mm spanner on the other side of the bolt, between the end of the drop link itself and the shock absorber. There is a rubber bushing there so it can be a little fiddly to get the spanner into place, you will know once it’s in place though. Now take a 16mm socket and undo the nut. The drop link will push away from its mounting and you can leave it to dangle for the time being.
Next you will have to undo the collar at the bottom of the shock absorber. This is an 18mm socket and it is on tight as it is all that is holding the hub to the suspension. I used a big breaker bar with an extension to loosen it sufficiently then got it out the rest of the way with an impact gun.
Now that’s out push down on the hub with your foot and it will fall away. All that is holding the old unit in place now is the three 13mm bolts at the top suspension turret under the bonnet. Loosen them but keep a grip on the shock absorber to stop it falling out. Gently remove it and take it away.
Putting the new one is pretty much the reverse of the process. Start at the top. Line the coilover up to the three holes in the suspension turret, it can only go in one way, and tighten the three bolts up.
Next is the drop link
And finally the collar at the bottom. Use your jack to raise the hub and the shock absorber holder thing (technical term) to where it need to be then put that bolt back in. Be sure that it is as tight as it physically can be because, as I said earlier, it’s the only thing holding the hub to the top of the suspension and you are going to have a very bad day if it comes out!
The backs are super simple to do! For some reason my camera decided not to save the progress shots at the back, which was nice of it, but I will talk you through how to do it.
There is a strut and then an external spring at the back. The strut holds the lower arm to the rest of the car and the spring is sat between the lower arm and the wheel arch.
Undo the bolt holding the strut to the lower arm and the lower arm will drop down allow you to safely remove the spring. Pull it out and put the new lower spring in there. now go into the boot of the car to undo the two bolts holding the strut up. Again make sure to hold onto the strut as you remove the bolts to stop it falling out. The does require having to sort of hug the back of your car and you will need fairly long arms but I have faith in you!
Once the old unit is out line the new strut up with the holes at the top, bolt it in place, jack the lower arm up and put the final bolt in. Job done!
Now to stand back and admire the results!
Thanks for reading! Good luck with installing your coilovers!