E86 Suspension - Help me understand the options

j3nks79 · Post by **j3nks79** » Sun May 05, 2024 4:30 pm

Getting off the 19’s for 18’s will greatly improve the ride quality.
I went sachs all round with Vogtland springs. Nice drop and still very comfortable.
I also replaced front arms and track control bushes along with inner and out track rods. Drop links and D bushes for the anti roll bar

Fred Smith · Post by **Fred Smith** » Sun May 05, 2024 5:10 pm

The options below seem to be some of the standard set-ups you might have. All prices are for the basics - dampers and coils. I am assuming £100 to £200 in sundries, plus labour if applicable, goes on top.

Bilstein B4 dampers with Suplex Standard coils - £650 [This option will cost me £290, only with reasonably new Sachs damper and unknown coils on the front] SE level

Bilstein B4 dampers with Suplex Sport coils - £710 [This option will cost me £450, only with reasonably new Sachs damper on the front] Sport Level

Bilstein B4 dampers with Eibach Performance coils - £700 [This option will cost me £440, only with reasonably new Sachs damper on the front] Lowered Sport Level

Koni Sport aka Koni Yellow dampers - £870 including springs for full set. [Broadly equivalent to a Bilstein B8]

Bilstein B6 dampers with Suplex Sport coils - £1,020. Sport Level Plus

Bilstein B8 dampers with Eibach Performance - £1,090. Lowered Sport Level Plus

Bilstein B12 kit - Bilstein B8 dampers with Eibach Performance (includes extras?) - £1,200. Lowered Sport Level Plus

Special Kay · Post by **Special Kay** » Sun May 05, 2024 5:31 pm

Lots of good options there Fred. Whatever, you choose will be great. Myself personally, I'd go with the B4s and the eibachs. But it's your car, and ultimately your choice.

Fred Smith · Post by **Fred Smith** » Sun May 05, 2024 5:38 pm

The obvious option for me is the cheap one.

I suppose my questions are -

How well do B4s work with Eibach performance, and what extra needs doing when fitting to ensure the B4s can cope with a non OEM coil? From what I have read it would be easy to install Eibachs with B4s and much reduce the life of the dampers. How do they compare comfort wise to SE level coils?

Sell me the idea of spending £1,100 or £1,220 on Bilstein B8s / Eibach.

How good are the Konis compared to other options?

I hope this thread is useful to others, my ultimate decision might be pretty simple and cheap, but if I go down that route I want to be clear what I'm missing out on and might get in future.

enuff_zed · Post by **enuff_zed** » Sun May 05, 2024 5:39 pm

Fred Smith, where are you based?
Are you planning to get a garage to do the work?
Happy to help you out with it if it keeps your costs down.

Fred Smith · Post by **Fred Smith** » Sun May 05, 2024 5:41 pm

Special Kay wrote: ↑Sun May 05, 2024 5:31 pm Lots of good options there Fred. Whatever, you choose will be great. Myself personally, I'd go with the B4s and the eibachs. But it's your car, and ultimately your choice.

I think that might be a good call, with my reservations being ensuring they're installed right so the non-OEM coils don;t reduce the life of the dampers, and that I am not sure how comfortable they are compared to SE stock. What is your experience?

Fred Smith · Post by **Fred Smith** » Mon May 06, 2024 6:57 pm

enuff_zed wrote: ↑Sun May 05, 2024 5:39 pm Fred Smith, where are you based?
Are you planning to get a garage to do the work?
Happy to help you out with it if it keeps your costs down.

I have updated the original post with more info.

Thanks for the message and chat!

Looking online it seems like the SE level Suplex rear coils and out of stock everywhere, AND the Lemforder rear top mounts are out of stock in many places, but seem to be on ebay! I don't suppose anyone knows anywhere that the Suplex are available, or where else the Lemforder's might be?

Can anyone recommend other brands of coil for a basic / SE level job?

Zedebee · Post by **Zedebee** » Mon May 06, 2024 8:01 pm

I’ve found Lesjofors springs to be fine (I’d be surprised if you could detect much difference between springs in ordinary driving) and used Sachs top mounts all round when I did my suspension over the winter. No knocking.

j3nks79 · Post by **j3nks79** » Mon May 06, 2024 8:02 pm

Sachs springs from Euro Car parts are good

Special Kay · Post by **Special Kay** » Mon May 06, 2024 8:03 pm

Who needs SE you can have Sport, or better still Eibach. Or just go all out and get coilovers. Or just go off on a tangent and get air ride fitted, low enough to cut the lawn, and high enough to go off road, all at the touch of a button

Fred Smith · Post by **Fred Smith** » Mon May 06, 2024 8:14 pm

Special Kay wrote: ↑Mon May 06, 2024 8:03 pm Who needs SE you can have Sport, or better still Eibach. Or just go all out and get coilovers. Or just go off on a tangent and get air ride fitted, low enough to cut the lawn, and high enough to go off road, all at the touch of a button

My decision is pretty simple and boring in the end... I have a cheap high mileage car and the cost of replacing the rear like for like is fairly low, whilst the cost of even a small upgrade doubles the cost (or more) as I also have to look at the more expensive front end as well.

I am typing this, with stuff in baskets online... and you're making me think again!

Fred Smith · Post by **Fred Smith** » Mon May 06, 2024 8:23 pm

j3nks79 wrote: ↑Mon May 06, 2024 8:02 pm Sachs springs from Euro Car parts are good

£140 for two rear sachs at euro car parts, compared to £225 best price I've found for four Eibachs! That's the sort of thing that makes it so much harder to actually decide what is best!

Can someone explain the bumpers for me and what I need to do to make sure that my garage does to ensure that the OEM Sachs damper on front and maybe rear, or Bilstein B4 on rear, don't get put under additional stress if I swap to Eibachs?

Also, has anyone else notice that there seem to be two types of Eibach for Z4 - one drops front and rear 30mm each (which I believe is only another 15mm lower than M-Sport level), and the other drops front 30mm and rear 20mm (literally only 5mm lower than M-Sport). Again, I might be misunderstanding but there oft-talked about Eibach lowering spring don't lower much, especially on the rear. Anyone know about the difference between the two rear shock options for Eibach?

Fred Smith · Post by **Fred Smith** » Mon May 06, 2024 8:25 pm

Zedebee wrote: ↑Mon May 06, 2024 8:01 pm I’ve found Lesjofors springs to be fine (I’d be surprised if you could detect much difference between springs in ordinary driving) and used Sachs top mounts all round when I did my suspension over the winter. No knocking.

Thank you - the Sachs look very very similar to Lemforder and genuine BMW. I can believe you on detecting differences on Springs... but then again I suspect longevity might not be a strong point of the cheaper springs, but maybe I am wrong. Thanks

Special Kay · Post by **Special Kay** » Mon May 06, 2024 9:12 pm

Hey Fred, if your keeping costs down is your priority, there is the option of just replacing the rear struts instead of replacing all four. Replace all top mounts and springs including other ancillaries to completely refresh your suspension.

Special Kay · Post by **Special Kay** » Mon May 06, 2024 9:32 pm

Hey Fred, I don't know whether or not you have the Autodoc App on your phone, but they are offering eibach's for £169.10 plus delivery. You'll have to be quick if you want to pursue that deal though. By the way, the prices online are always more expensive in comparison to the app for some reason. Good luck

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