[JoshU]

So I have a 2015 430d (pre lci) currently up to 79,000 miles (127,000km). I'm looking to lower my car for aesthetics and fit springs, perhaps acs or eibach?

However due to the age and mileage of the car are the shocks likely to be an issue I should replace as well or will just the springs be ok?

If so what setup would you suggest to keep the costs reasonable.

I'm also looking to not do anything to worsen the ride of the car, I already find it very crashy and I'm looking to change to non run flats to try to counter that.

I have adaptive suspension too, if that changes anything.

[cfm56d7b]

What's your budget for the suspension upgrade including installation and 4 wheel alignment?

[JoshU]

I wouldn't say I have a strict budget as such but I was hoping I could get it all in under £1500 (if I went for the full spring&shock refresh).

[SuperLomi]

If you are doing the install yourself, I'd say it's up to you, and how you value your time down the road, unless the struts are determined to actually be bad.

If someone else is installing, I'd consider doing everything you can now, to save on labor cost doing it again later.

[JoshU]

I'm leaning more towards the all or nothing route at the moment to be honest.

Not sure exactly what my best route would be though. I'm not looking to make the car have less body roll or become a track beast or anything, just looking to have the lowered look and maintain or even improve the comfort of the car really.

Do you have any suggestions about the best route. From a lot of what I've seen on here Acs/eibach springs with a bilstein dampers seems a popular choice.

Thanks for the reply!

[tj_g]

I’ve just ordered mine after a ton of research. Not that that means I’ve made the best choice, but here’s my summary:

TLDR: KW Street Comforts £1231 + £300ish fitting.

I’m on 90k miles, passive suspension. I’m convinced the shocks are worn and not dampening properly, so I was a definite for shocks and springs.

I also wanted to lower the car for aesthetics, and to sort out the wallowy front end (it’s a 330d x drive F31)

Didn’t want to make it into a track king, maintaining comfort was key.

Options

All costs are for the kit only. Install is anything from £200-£350

Bilstein B12 (Eibach Pro Kit). Can be had for £650ish

ACS springs and B8 dampers £8-900 I think

The B8’s aren’t custom tuned and seem to be quite hard / crash at low speeds and then don’t dampen particularly well at high speeds

ACS springs and Koni Special Actives £8-900
Quite gentle at low speeds and good dampening at higher speeds.

Check out the info in this thread for the different shock options
https://f30.bimmerpost.com/forums/sh....php?t=1662711

Bilstein B14. £8-900 IIRC. Coilover system so you can dial in your ride height just how you want it.
However the shocks are quite firm and the spring rate is higher than OEM so overall probably too firm

KW Special Actives.
I went with these.
Apparently the spring rate is near OEM and you have adjustable rebound on the shocks so you can get a good level of comfort.
Coilover so adjustable ride height.

I was at the top of my budget with the KW SC’s - I waited for Black Friday which gave £200 off their £1431 usual price. To be fair you could usually find them for £1300ish at a few retailers.

If you can push your budget further then the ACS Sport system is apparently a great option. It’s fixed shocks and springs, ie not a coilover so no adjustable ride height, but by all accounts it’s tuned perfectly to the car for the right drop and the OEM+ level of comfort and handling.
I believe the springs are based on Eibach - you will see posts on here saying they’re just re badged Eibachs but I understand that this is not correct - they’re custom spec’d and manufactured and suit the car perfectly.
Same with the dampers - they’re a custom valved unit based on the Bilstein B8, again, tuned to the F3x.

Above that is the ACS RS which is a KW V3 based coilover system - different price bracket.

If I had more budget, I’d have seriously considered the ACS Sport.

I didn’t research Birds, but they do get a good rep on here too.

Good luck!

[cfm56d7b]

Originally Posted by JoshU

I'm leaning more towards the all or nothing route at the moment to be honest.

Not sure exactly what my best route would be though. I'm not looking to make the car have less body roll or become a track beast or anything, just looking to have the lowered look and maintain or even improve the comfort of the car really.

Do you have any suggestions about the best route. From a lot of what I've seen on here Acs/eibach springs with a bilstein dampers seems a popular choice.

Thanks for the reply!

Improved comfort + suspension lowering = are conflicting goals.

Comfort is a function of ...
- Sufficient suspension travel
- Sufficient enough for compression and rebound cycles to absorb road imperfections while maintaining suspension geometry without bouncing up and down

Lowered suspension has less travel and that _usually_ means less comfort.

Coilovers with independent compression and rebound controls - ex: KW V3 - offer enough tuning options to help you find the optimum balance between performance and comfort.

[Emerson335]

@JoshU, I had very similar goals as you last year with my '15 335xi

I went the following;
* Eibach 05-22 springs (European kit, slightly lower than the Eibach 06-22 kit)
* Koni Yellow struts (I did not have adaptive suspension)
* Replaced the factory F30 bump stops with factory F80 bump stops from local BMW parts dept.

I'm very happy, nothing I regret with the path I took. I will say I was concerned with the ride quality, however it was not as harsh as I feared and the handling was much better. I will say that road imperfections were a lot more noticeable after being lowered. However I just recently replaced my wheels/tires, and went with a meatier non-run flat tire and it made a huge improvement to the ride quality and I would argue it is now practically the same ride quality as factory suspension with factory run flats.

If you consider going the Eibach route, I recommend looking at this thread;
Any EIBACH SPRINGS on F30 335i X-DRIVE? https://f30.bimmerpost.com/forums/sh....php?t=1501682

Also, if looking to do the install yourself (I did, and I would not consider myself a mechanic by any stretch) I highly recommend this incredible video from Farkle;

[gds]

Nice review. I would like to ask what tires do you use and the dimensions of tires and wheels that you used before(the run-flat ones).I m on 225/45/18 R/F Bridgestone potenza S001, Koni yellow, normal m sport springs and Eibach sway bars and the ride is not good in low, city speeds.

[gds]

Originally Posted by Emerson335

@JoshU, I had very similar goals as you last year with my '15 335xi

I went the following;
* Eibach 05-22 springs (European kit, slightly lower than the Eibach 06-22 kit)
* Koni Yellow struts (I did not have adaptive suspension)
* Replaced the factory F30 bump stops with factory F80 bump stops from local BMW parts dept.

I'm very happy, nothing I regret with the path I took. I will say I was concerned with the ride quality, however it was not as harsh as I feared and the handling was much better. I will say that road imperfections were a lot more noticeable after being lowered. However I just recently replaced my wheels/tires, and went with a meatier non-run flat tire and it made a huge improvement to the ride quality and I would argue it is now practically the same ride quality as factory suspension with factory run flats.

If you consider going the Eibach route, I recommend looking at this thread;
Any EIBACH SPRINGS on F30 335i X-DRIVE? https://f30.bimmerpost.com/forums/sh....php?t=1501682

Also, if looking to do the install yourself (I did, and I would not consider myself a mechanic by any stretch) I highly recommend this incredible video from Farkle;

Nice review. I would like to ask what tires do you use and the dimensions of tires and wheels that you used before(the run-flat ones).I m on 225/45/18 R/F Bridgestone potenza S001, Koni yellow, normal m sport springs and Eibach sway bars and the ride is not good in low,city speeds.

[Emerson335]

Originally Posted by gdsalepis

Nice review. I would like to ask what tires do you use and the dimensions of tires and wheels that you used before(the run-flat ones).I m on 225/45/18 R/F Bridgestone potenza S001, Koni yellow, normal m sport springs and Eibach sway bars and the ride is not good in low, city speeds.

When I lowered the car back in May I had the stock 18" 400M wheels (square) with factory Conti RFT's 225/45-18 that were end of life. I was also running 12/18mm spacers F/R.

A few weeks ago I switched to APEX 18x9 ET30 ARC-8 wheels (square) with non-RFT high performance all season Conti DWS-06 Plus 255/40-18's. This kept my same rolling diameter, did not increase wheel gap, and I'm super happy with the decision. This is the largest square setup I could fit on my car, I'm not rubbing however just barely as there is no additional space up front.

FWIW- I had planned to go the Michelin route, however the Conti's had a better price, better lifespan, American made, and were highly recommended. I also liked the previous Conti's, with the exception they were RFT's.

[JoshU]

Originally Posted by tj_g

Options

All costs are for the kit only. Install is anything from £200-£350


ACS springs and Koni Special Actives £8-900
Quite gentle at low speeds and good dampening at higher speeds.

Check out the info in this thread for the different shock options
https://f30.bimmerpost.com/forums/sh....php?t=1662711


KW Special Actives.
I went with these.
Apparently the spring rate is near OEM and you have adjustable rebound on the shocks so you can get a good level of comfort.
Coilover so adjustable ride height.

I was at the top of my budget with the KW SC’s - I waited for Black Friday which gave £200 off their £1431 usual price. To be fair you could usually find them for £1300ish at a few retailers.

Thanks so much for this informative post first of all, great details and you've helped make my mind up with these suggestions. I've had a further look into the Koni SA/ACS combo and also the KW SA and I think one of these will be exactly what I'm after. I'd love to hear your feedback on the KW's once they're fitted and you've done a few miles in them.

Also if you could tell me where you got them for such a great price or have any particular places you'd recommend for purchasing these sort of things it would be appreciated.

I'm leaning more towards the Koni/ACS combo just for the simplicity and price I think but it's ever so close and I could certainly sway either way. I just need to decide and then find a good garage in the Oxfordshire or Sussex area.

I will also have to code out my EDC but that should be simple enough.

Originally Posted by cfm56d7b

Improved comfort + suspension lowering = are conflicting goals.

Comfort is a function of ...
- Sufficient suspension travel
- Sufficient enough for compression and rebound cycles to absorb road imperfections while maintaining suspension geometry without bouncing up and down

Lowered suspension has less travel and that _usually_ means less comfort.

Coilovers with independent compression and rebound controls - ex: KW V3 - offer enough tuning options to help you find the optimum balance between performance and comfort.

I think I worded my post badly, I'm not necessarily looking to gain comfort just from the hardware change but also because my suspension should be coming to the end of its life and a refresh would prevent the crazy skipping I get when I go around a corner with a tiny bump on it, for example.

Originally Posted by Emerson335

@JoshU, I had very similar goals as you last year with my '15 335xi

I went the following;
* Eibach 05-22 springs (European kit, slightly lower than the Eibach 06-22 kit)
* Koni Yellow struts (I did not have adaptive suspension)
* Replaced the factory F30 bump stops with factory F80 bump stops from local BMW parts dept.

I'm very happy, nothing I regret with the path I took. I will say I was concerned with the ride quality, however it was not as harsh as I feared and the handling was much better. I will say that road imperfections were a lot more noticeable after being lowered. However I just recently replaced my wheels/tires, and went with a meatier non-run flat tire and it made a huge improvement to the ride quality and I would argue it is now practically the same ride quality as factory suspension with factory run flats.

If you consider going the Eibach route, I recommend looking at this thread;
Any EIBACH SPRINGS on F30 335i X-DRIVE? https://f30.bimmerpost.com/forums/sh....php?t=1501682

Also, if looking to do the install yourself (I did, and I would not consider myself a mechanic by any stretch) I highly recommend this incredible video from Farkle;

I hadn't really considered fitting it myself but I have have a look further into it for sure, and if I do that video will be where I start so thanks.

It appears you've gone for a sportier setup than the one I'm after however I'm interested in your tire solution - I love the look of the meaty tired you're running. I'm staggered with 225/40/19 and 255/35/19 and wondering how I could get a similar look while probably preferring to remain staggered.

[Emerson335]

Originally Posted by JoshU

I hadn't really considered fitting it myself but I have have a look further into it for sure, and if I do that video will be where I start so thanks.

It appears you've gone for a sportier setup than the one I'm after however I'm interested in your tire solution - I love the look of the meaty tired you're running. I'm staggered with 225/40/19 and 255/35/19 and wondering how I could get a similar look while probably preferring to remain staggered.

I would check out APEX's online fitment guides (F30 link below), I found them very helpful. Plus the guys at APEX are super helpful & patient with any questions you have.

I originally was going to go the staggered route as well, however the combination of not being able to rotate along with the added consideration of X-drive I opted to go the more conservative route with a square setup.

https://support.apexraceparts.com/hc...-Fitment-Guide

P.S. here are two pics of my front tire for reference, if it helps.

[Watsey]

To the OP.

It depends on your wants/needs, i.e. whether you are simply looking for aesthetics or whether you want to improve the dynamic capabilities of the car, but from direct experience I'd be wary of going down the ACS route if you opt for 'springs only'.

Plenty of people have found the ACS springs to be fine, but I found them to be not a big enough improvement (spring rates) to be worthwhile. In short, they were too soft. It also didn't help that I retained the OEM adaptive dampers which were either under-damped (Comfort) or too too stiff (Sport). BMW may have improved the system since my 2012 car, but on the pre-LCI cars the dampers are a real weak point.

I'm not advocating super-stiff springs and a rock-hard ride - that can be really detrimental.

I ended up having the springs and dampers replaced with a far better setup (Ohlins).

As with any significant cost, do your research first. It's not something you'll want to do twice. I'd strongly recommend changing the springs and dampers at the same time and making sure, as best you can, that you select well-matched units.

[Kooner23]

Not sure about the pricing for ACS springs over there, but why not go for the Eibachs springs instead. For my F30 I went with the Eibach 05-22 springs and I'm pretty sure they are the same or very close as the ACS, just a lot cheaper.

I went with the Bilstein B4 struts, and the OEM struts were definitely on their way out with only 90,000kms. So 100% recommend switching those out.

[JoshU]

So following the info gathered from this thread and my own research online I've opted for a full refresh with KW Street Comforts which I picked up at a great price.

Quite excited to see the look of the car lowered and with 10/12 spacer setup. And even more so looking forward to the improved handling and ride.

I wonder if anyone has any experience with the EDC delete - I'm buying the coil overs without any delete kit and going down the coding route, I assume the fitment will be fine and just chuck up a few error codes I can ignore until I sort get it to a coding specialist?

Also just on the off chance anyone else has fitted these coil overs, how did you set it up with regards to damping? Just something in the middle?