You have ordered your new suspension from us, want to install it yourself at home and have never installed a chassis yourself? No problem! With this guide, nothing stands in the way of installing your MX-5 coilovers! We ourselves install MX-5 suspensions on a daily base and can therefore be of assistance and advice if you want to assemble your suspension in your garage at home. These instructions apply to all MX-5 models.
The important things first:
Ideally, the coilover system should always be installed by a professional workshop. These are safety-relevant components on your car. If you feel confident about installing the suspension yourself, you can use this guide to do the installation yourself. However, installing the suspension always involves wheel alignment. By changing the ride height and loosening the rubber bushings, you change and adjust all wheel alignment values that have to be set later by a workshop. You should therefore pay attention to this, because otherwise, on the one hand, the advantages of your suspension system will not come into their own and the car will no longer drive nicely, and on the other hand, the tires will wear out very quickly. So here you should definitely do the wheel alignment directly after installing the chassis.
Removing the old suspension:
First we start by loosening all screws of the wishbones with rubber bushings. Ball bushings do not have to be loosened. The reason for this is that the bushings should be tension-free in the vehicle and has the advantage that, on the one hand, the suspension can be removed more easily and, on the other hand, the bushes have already been loosened for later releasing the bushes. From this moment on, wheel alignment is necessary, but it cannot be avoided if you simply skip this step. In addition, strained bushings usually tear out, which entails significantly more costs and work than wheel alignment.
The old suspension can then be removed.
Now we start with the rear axle:
To do this, the lower fastening screw of the shock absorber must be loosened and removed. Carefully open the screw on the MX-5 NA / NB / NBFL! On the inside of the wishbone (at the end of this screw) sits a square nut, which likes to tear out of its cage and then simply turns with the screw. If the nut turns, it can be held in place with a wrench (possibly ground off) and the screw can be removed. The plastic cover to the front of the vehicle and the metal cover of the tank pipe in the trunk can then be removed in order to gain access to the top mount attachment. Unscrew the two outer nuts here. With the last nut in each case, the suspension can be held in place trough the wheel arch so that the suspension does not simply fall off when the nut is removed.
After this we go further to the front axle:
First we loosen the fastenings of the brake line and ABS cable on the upper wishbone for NC and ND. Then the lower fastening screw of the shock absorber can be loosened and removed. Then unscrew the inner fastening screws of the upper wishbone (with NA / NB / NBFL the anti roll bar must be loosened so that the screw can be pulled out towards the front). Then loosen the top mount fastening of the shock absorber. The shock absorber can then be removed from the upper wishbone by tilting it outwards.
Now we prepare the new suspension to mount it in the car:
These steps are described in detail in our installation instructions and are therefore "skimmed over" a little. First you set the desired spring preload on the shock absorber. This is done using the upper 2 adjusting nuts on the shock absorber, the upper one is for adjusting, the lower one counteracts and secures the upper nut on the thread so that nothing is misaligned while driving. You can then adjust the vehicle height. To do this, you simply have to screw or unscrew the entire shock absorber into the lower damper sleeve and secure it with the lowest threaded ring after the setting is complete. Please note the minimum and maximum values in your report so that there are no problems with the TÜV-entry later. Finally, we set the damper hardness using the upper knurled nut on the top mount of the suspension. This can also be adjusted later in the installed state, but it is more convenient to make the basic adjustment as long as the suspension is on the workbench anyway. There are also tips for a good basic setting in our installation instructions.
As soon as each coilover is prepared, we start with the installation:
Everyone knows the expression "installation takes place in the reverse order" from installation instructions, but we will go through the points here again step by step so that you do not forget anything and, if necessary, drive off with a loose suspension.
So let's start with the installation on the rear axle:
The coilovers can simply be inserted and secured with the lower damper mount (90 Nm torque). Then you thread the top mounts into the attachment on the car, this is best done with a second person or a jack that you attach under the lower wishbone. You can then pump it up until the studs are completely in the holes in the vehicle and then fasten the nuts in the trunk (approx. 40 Nm torque).
When you have attached all the coilover fixings to the rear, you can continue on the front axle:
Here you can thread the damper back into the upper wishbones and secure them with the lower fastening screw (90 Nm torque). Then bring the upper wishbone back into position and insert the screw (or the two screws for NC and ND) through the wishbone again. You don't have to tighten this yet, as we will release all the bushings afterwards anyway. For the MX-5 NA / NB / NBFL, please remember to reattach your anti roll bar. With the NC and ND, remember to reattach the brake lines and ABS cables. Then you can push the suspension upwards, just like on the rear axle, to attach the nuts to the studs of the top mounts (approx. 40 Nm torque).
If all bushes are only loosened and the screws are not completely unscrewed, we can now take a first look at your future ride height. To do this, you attach the wheels to the vehicle and set the car down on the ground. Then rock the car a bit at the front and back so that the suspension can sit down a little. Now the necessary measurements can be made as described in the installation instructions so that your new ride height does not cause any problems when TÜV-entering it.
If you are satisfied with the height of the vehicle and TÜV-compliant, you can relax with the bushes:
The rubber bushings have to be relaxed because they are pretensioned (if you don't relax them) due to the new ride height. These can then tear during compression. In addition, if the bushes are not relaxed, they do the work that should actually be done by the suspension itself and the vehicle does not drive nicely.
The bushings are getting relaxed for each axle, while the other axle stands on the wheels on the floor to secure the car.
To do this, place the respective axle on jack stands (as far out as possible on the wishbone) and then tighten all of the axle's bushings. Here it is a good idea to mark the screws so that you don't forget a screw or bushing.
Setting down on jack stands has the consequence that the bushings are now in their "rest position" at the new ride height and therefore do not tear when deflecting through cornering or potholes. After you've completed this process on both axles, you can reassemble the wheels. Then roll the car a few meters forwards and backwards so that the suspension can settle. Then you can check the ride height again and cross the vehicle and you are actually ready for the wheel alignment.
Wheel alignment:
As already mentioned above, wheel alignment after the coilovers have been installed is indispensable. We have listed our standard values for you here, so that you know which values the alignment company should set so that you have an optimal axle setting for your chassis:
Daily Driver Alignment:
Rear axle:
- Toe: +18 minutes total (+9 minutes per side)
- Camber: -1°30 per side
Front axle:
- Caster: 6°00 minutes
- Camber: -1°20 per side
- Toe: +12 minutes total (+6 minutes per side)
Sport Alignment:
Rear axle:
- Toe: +20 minutes total (+10 minutes per side)
- Camber: -2°00 per side
Front axle:
- Caster: 6 ° 30 minutes
- Camber: -1°45 per side
- Toe: +12 minutes total (+6 minutes per side)
Racing Alignment:
Rear axle:
- Toe: +20 minutes total (+10 minutes per side)
- Camber: -2°30 per side
Front axle:
- Caster: 7°30 minutes
- Camber: -2°45 per side
- Toe: -10 minutes total (-5 minutes per side)
If you have any questions about installing the suspension, feel free to post a comment on this blog or send us an email, we will be happy to help!
Your SPS Motorsport Team