Upgrading Suspension on BMW E90

Upgrading Suspension on BMW E90

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RobM77

Original Poster:

35,349 posts

233 months

Friday 25th November 2016
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I've just bought a 2010 E90 320d ED and it's great. It satisfies my needs of being quiet on the motorway (16" wheels), not too grippy (16" wheels!) and good mpg (I'm averaging close to 70mpg...). I also already have 16s with winter tyres fitted. The trouble is that the ride and handling isn't very good; it understeers quite a lot and bounces up and down like a pogo stick on bumpy lanes. I want to uprate the suspension, but what I definitely don't want to do is upsize the wheels, I want to stick with 16s.

Can anyone comment on my options? The BMW specialist that I use says he can fit 'sports' suspension or 'M Sports' suspension, but I understand these are designed for 17" wheels - would I run into problems running 16s? I presume the car would be lowered by 13mm (half in inch) compared to standard M Sport and ED, which both run 15mm lower. M Sport cars also appear to have wider rear tyres, whereas I'd be running the same all round - any comments on that?

The other option is aftermarket - Bilstein, Koni etc.

Any thoughts?

phil_cardiff

7,043 posts

207 months

Saturday 26th November 2016
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Are you on runflats? Changing them helps the ride a bit.

When I had my E91 I looked into Birds suspension packages or Eibach springs with Koni FSD dampers but sold the car before going for it.

Wombat3

11,973 posts

205 months

Saturday 26th November 2016
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Are you on Run flats? The suspension on these things is designed to work with Runflats. If you put non run flat tyres under it then its going to feel soft I think.

I know loads of people swear by putting non runflat tyres on BMWs but its not the way it was designed to work.....

Are the current shocks actually working properly or are they just knackered?

zippyonline

354 posts

165 months

Saturday 26th November 2016
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If you look through my posts (I haven't made many on PH, normally a long time lurker) you'll see I've had some trouble with my E91....

However, I have driven for a several hundred miles both a E90 320D SE with standard suspension, an E90 320ED with the ED suspension and also currently own my E91 330i with the birds suspension. Now we'll ignore my car with the birds setup for now, as it clearly has some issues I need to work out and sort, but my experience from driving the other two.

The SE suspension I found quite amicable really, it settled over bumps reasonably well and was fairly alright - I never did push it near the limit though, so don't know what it's like there.

The 320Ed had a slightly lower suspension (eeking out mpg and aero to meet tax bands maybe?), but it really wasn't as good a drive as the SE, it grounded easily over bumpy rounds and didn't settle very quickly, as well as being more harshly sprung.

Those were my observations anyway - if you're doing it yourself, maybe check out the part no's on realoem and try a set of SE suspension depending on what you can get hold of price wise etc.?

RobM77

Original Poster:

35,349 posts

233 months

Sunday 27th November 2016
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Thank you very much for your replies.

I'm not on RFTs, no, but this is standard for the ED. I agree entirely regarding these; my previous car, which I sold on Wednesday, was a pre facelift E90 SE and the RFTs were fine. As you say, the tyre sidewall is a significant part of the suspension, so it's all tuned together. The ride when changing to my non-RFT winters was definitely worse.

My pre facelift E90 SE had really nice handling, yes. If I'm changing the suspension on my ED though then if the outlay is similar I'd like to go a stage further than the SE. Whilst on the motorway I value quiet and economic driving, on B roads and twisty roads I value handling above all else. I'm a huge fan of the E92 M3, but just can't justify the outlay given how little performance matters to me in a road car.

The Birds kit is of great interest, so thank you for suggesting it. I'd forgotten that they offered this. I've been disappointed by the focus on lowering and looks by other aftermarket kits, so this one's focus on road driving really appeals to me. I'll phone them on Monday.

The Wookie

13,909 posts

227 months

Wednesday 30th November 2016
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In my experience (and off the top of my head as I haven't driven any standard ones recently), most BMW's of that era are mismatched in bump and rebound and end up being busy with the propensity to fire themselves up in the air on bigger, soft edged inputs.

The M-Sport suspension generally has more control over the vertical movement but still demonstrates the same behaviour and with a tendency to react more harsly to sharper inputs like potholes.

Putting smaller wheels for higher profile tyres improves the rolling comfort and reduce the business but wont affect the vertical control, in fact will probably make the size of the movement worse if slightly slower.

The only E90 I've driven that felt well sorted with a nice, flat ride and without excessive harshness (and without having an expensive aftermarket system on it) was a mate's Alpina D3 Bi-turbo on 18" wheels and non-RFT tyres. If you can get hold of the springs and dampers from one of those then I'm sure you'd approve.

RobM77

Original Poster:

35,349 posts

233 months

Wednesday 30th November 2016
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Thanks Wookie, I've just e-mailed Alpina UK.

My Birds quote was £1600 for springs, dampers and ARBs, that's parts only minus fitting. Kevin Bird said he would normally advise against uprating the ARBs without an LSD, but given the low power output of my car he thought it would probably be ok. The issue is the lightly loaded inside wheel spinning away the power.

The Wookie

13,909 posts

227 months

Wednesday 30th November 2016
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RobM77 said:
Thanks Wookie, I've just e-mailed Alpina UK.

My Birds quote was £1600 for springs, dampers and ARBs, that's parts only minus fitting. Kevin Bird said he would normally advise against uprating the ARBs without an LSD, but given the low power output of my car he thought it would probably be ok. The issue is the lightly loaded inside wheel spinning away the power.
Probably tells you all you need to know about the compliance of that setup!

RobM77

Original Poster:

35,349 posts

233 months

Wednesday 30th November 2016
quotequote all
The Wookie said:
RobM77 said:
Thanks Wookie, I've just e-mailed Alpina UK.

My Birds quote was £1600 for springs, dampers and ARBs, that's parts only minus fitting. Kevin Bird said he would normally advise against uprating the ARBs without an LSD, but given the low power output of my car he thought it would probably be ok. The issue is the lightly loaded inside wheel spinning away the power.
Probably tells you all you need to know about the compliance of that setup!
Perhaps, yes! I could always go with just the springs and dampers. Apparently the springs are a touch softer than M Sport and they then spent a while speccing the dampers to suit.

BMW constantly surprise me. Sometimes BMW come up with a beautifully judged setup (e.g. the E90 M3, my old E36 328i Sport, and even my 2007 pre-facelift E90 SE was pretty decent), but sometimes they're awful: my ED for example is the worst handling BMW I've ever driven, and my Z4C would just never settle on a bumpy road; it was a 1320kg FE/RWD car with a super stiff chassis, so I've no idea why they couldn't make it ride in the same ballpark as an Evora or even a Cayman.

The Wookie

13,909 posts

227 months

Wednesday 30th November 2016
quotequote all
RobM77 said:
Perhaps, yes! I could always go with just the springs and dampers. Apparently the springs are a touch softer than M Sport and they then spent a while speccing the dampers to suit.

BMW constantly surprise me. Sometimes BMW come up with a beautifully judged setup (e.g. the E90 M3, my old E36 328i Sport, and even my 2007 pre-facelift E90 SE was pretty decent), but sometimes they're awful: my ED for example is the worst handling BMW I've ever driven, and my Z4C would just never settle on a bumpy road; it was a 1320kg FE/RWD car with a super stiff chassis, so I've no idea why they couldn't make it ride in the same ballpark as an Evora or even a Cayman.
Probably vehicle dynamics by numbers (i.e. marketing let subjective and objective handling targets fulfilled by committees of dynamics engineers each on separate aspects of the car) combined with nice smooth German roads to tune on. We want it sporty but comfortable, stable but agile, fun but safe, etc.

Even the E90/92 M3 displays a few traits of it. Ever noticed how the steering is feather light at parking speeds but heavy on the move? You can bet the marketing department targeted light parking efforts but 'sporty' weight. Borrowed a mate's E92 when I was at my old job, drove me insane after 2 weeks as every time I turned across the mini-roundabout at security it would be different every time as it was more or less than whatever arbitrary speed they had chosen for the changeover.

Lotus (and M division to a lesser extent) produce more coherent setups because they have a small team of guys responsible for the whole vehicle setup who have more authority in terms of subjective choice on where the car ends up. It also helps that typically on those sorts of cars there is more customer tolerance for shortcomings in a few areas, whether it's ride, stability, and even durability or 'safe' limit handling to some extent.

Case in point; I had my Cayenne geo'd earlier before a tyre change and it was miles out, cambers, toes, front, rear, everything. It took the garage I use 3 hours to sort it. I drove it home and even paying attention it only felt fractionally more stable on the motorway and linear in its responses in cornering. My Evoras would drive me bonkers if they were slightly out of spec, even on fresh tyres they would tramline dreadfully and the handling balance would shift quite obviously. Obviously there's a big difference in car type but you can bet Porsche wouldn't accept that sort of sensitivity in the 911 and indeed my experience of my old man's 997 Turbo is that it knocks out tyres in an unusual way long before it starts feeling significantly iffy on a fresh set of boots.

RobM77

Original Poster:

35,349 posts

233 months

Thursday 1st December 2016
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Thanks for the insight. smile

I've heard back from Alpina. They tell me that they're 'a manufacturer of exclusive automobiles' and are not 'a tuner or supplier of accessories'. They pointed me to Birds or Schnitzer.

The Wookie

13,909 posts

227 months

Thursday 1st December 2016
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Helpful! Probably better off just looking up the part numbers on the BMW system, rumour has it that they're a cunning mixture of other BMW range parts rather than a bespoke offering, although I'd expect the dampers to be unique!

ETA - Winner:

http://www.klinika-bmw.pl/alpina-pdf/katalogi/comp...

ETA Again after not being able to find the springs, rumour has it they use the 330d X-Drive springs weirdly? Don't take my word for it!

Edited by The Wookie on Thursday 1st December 15:58

helix402

7,832 posts

181 months

Saturday 3rd December 2016
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Last time I worked on one Alpinas used Eibach springs made to their specs.

RobM77

Original Poster:

35,349 posts

233 months

Thursday 11th May 2017
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An update for you: I've done a fair bit of research over the last few months and yesterday had Birds springs and dampers fitted, together with their anti-roll bars, and this morning I had a full geo done. The difference, as you can imagine, is startling. I had been putting it off due to the cost of the Birds kit (with the ARBs it was £1600 in parts alone!), but recently my suspension had degraded to the point where it was actually quite dangerous, especially towing (I tow a covered trailer with an all up weight of 1350kg), and given the cost of MSport suspension and its mixed reviews I figured it was worth spending a bit more given the Birds kit's overwhelmingly favourable reviews.

So, relatively it's obviously a complete revelation. In absolute terms though, compared to other cars I've driven (including M3s), I'm extremely pleased with it. Of particular note are the uprated anti-roll bars, which curb roll to a huge degree in corners.

I realise it's a bit odd having a wheezy diesel engine with suspension like this, but given my obsession with handling and disinterest towards performance, it suits me perfectly.

I was initially worried that the much lower unsprung mass of my 16" wheels and eco tyres would prove too different to Birds' customer's usual 19"ers with sticky sport tyres, not to mention my car's much lower kerb weight, but it feels fine to me. Sure, it's probably slightly more optimal on a big fat 335i, but until someone designs suspension specifically for a 320d running on the smallest wheels and tyres possible (which isn't going to happen!), it's the perfect solution.

phil_cardiff

7,043 posts

207 months

Thursday 11th May 2017
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RobM77 said:
An update for you: I've done a fair bit of research over the last few months and yesterday had Birds springs and dampers fitted, together with their anti-roll bars, and this morning I had a full geo done. The difference, as you can imagine, is startling. I had been putting it off due to the cost of the Birds kit (with the ARBs it was £1600 in parts alone!), but recently my suspension had degraded to the point where it was actually quite dangerous, especially towing (I tow a covered trailer with an all up weight of 1350kg), and given the cost of MSport suspension and its mixed reviews I figured it was worth spending a bit more given the Birds kit's overwhelmingly favourable reviews.

So, relatively it's obviously a complete revelation. In absolute terms though, compared to other cars I've driven (including M3s), I'm extremely pleased with it. Of particular note are the uprated anti-roll bars, which curb roll to a huge degree in corners.

I realise it's a bit odd having a wheezy diesel engine with suspension like this, but given my obsession with handling and disinterest towards performance, it suits me perfectly.

I was initially worried that the much lower unsprung mass of my 16" wheels and eco tyres would prove too different to Birds' customer's usual 19"ers with sticky sport tyres, not to mention my car's much lower kerb weight, but it feels fine to me. Sure, it's probably slightly more optimal on a big fat 335i, but until someone designs suspension specifically for a 320d running on the smallest wheels and tyres possible (which isn't going to happen!), it's the perfect solution.
Good to hear. I hope to return to an E91 (petrol) one day and Birds suspension is top of my list of things to do to it.