Car Throttle did a video on Eibach coilovers for their BMW project car. Car Throttle sell Eibach coilovers on their online shop for around 1050 GBP.
The Eibach Pro Street S coilovers are height adjustable only. So are they over priced?
The main features of the Eibach coilovers
No top mounts, uses the original top mounts.
Height adjustable with spring seat
Not damping adjustable (fixed damping)
In More Detail
Before we get into the analysis of the Eibach coilovers, what other coilovers are available on the market? What do they cost? And what features do they have?
Also on the Car Throttle online shop are BC coilovers.
The price on the BC coilovers is around 850 GBP
Main features of the BC Coilovers
Supplied with top mounts (adjustable if applicable)
Height adjustable with spring seat
Height adjustable with bottom mount
Damping adjustable for soft and hard
BC vs Eibach
On the face of it the BC are around 200 GBP cheaper and have more adjustability.
Eibach in detail
The Eibach coilovers are not adjustable for damping. This means you are stuck with the ride comfort that Eibach say is the best. Depending on where you drive, this may be great, this may be terrible. Either way you are stuck with the hardness from Eibach.
If the dampers were adjustable you could tailor the ride comfort to your preference and the roads/tracks you drive on.
Eibach make no mention of any special technology in the dampers eg dual rate valve in the dampers so in my opinion, not having damping adjustability is a huge negative for a coilover, there is a big risk they will simply be too hard for me.
In short, I don’t see the Eibach dampers having any benefit over the cheaper BC coilovers.
Eibach are one of the world’s leading manufacturers of springs. It’s safe to say that the springs on the Eibach coilovers will be better than the BC.
Are the springs on their own worth paying an extra 150 Euro?
In my opinion, no, the lack of damping adjustability is a much bigger issue, in short, I am prepared to compromise on spring quality to get damping adjustment
In the Car Throttle video, Eibach make a big deal about height adjustment and how you have to be careful with setting the ride height because the lower you go the less bump travel you have. If you run out of bump travel the suspension will hit the bump stops, massively increasing the effective spring rate in the suspension leading to potentially unpredictable handling.
With the Eibach coilovers height adjustment is limited.
With BC coilovers on the other hand, height adjustment is done via the bottom bracket meaning adjusting the ride height has no effect on the bump travel of the suspension.
Another plus for BC (the cheaper) coilover kit.
How important is height adjustment?
In reality, the suspension of most cars operates at its optimum within around 35mm of the cars original ride height. Any lower or higher than this and suspension geometry can be negatively effected reducing the performance of the car.
While it is nice to have a big range of height adjustment, the reality is you probably don’t need it (at least for performance) so while the BC has an advantage with height adjustment over the Eibach, its not that big of a deal (but still an advantage)
Eibach do not supply their Pro Street S coilovers with top mounts which saves them money. BC do supply their own top mounts with their coilover kits. This should make the price of the Eibach closer to the BC….
Why would you choose Eibach coilovers?
If you are concerned about the resale value of your car with coilovers installed, I don’t think anyone will argue that having Eibach is not going to negatively effect the car’s value. BC on the other hand probably will. Eibach is simply a more prestigious brand. If your car is worth tens of thousands of pounds, the price difference between BC and Eibach is irrelevant compared to the value of your car so the extra cost of the Eibach is completely irrelevant.
The springs on the Eibach coilovers will probably be superior in consistency of performance but I think that will pale into insignificance because the adjustable dampers of the BC will have a much more noticeable effect on the cars performance
In all other cases I do not see a reason to choose Eibach over BC. You get more for less with BC coilovers