My Suspension quest! 130i

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Dan258
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Re: My Suspension quest! 130i

Post by Dan258 » Tue Jun 12, 2018 2:46 pm

THETYRANT wrote:
Tue Jun 12, 2018 1:29 pm
Dan258 wrote:
Tue Jun 12, 2018 12:26 pm

Then it's a case of what springs/dampers... a fair few pages ago, I think Ian listed the Eibach pro spring lengths for the 135 e82, e88 and 130i (shortest to longest). Ideally, I'd like my car slightly lower so was thinking of getting hold of either the e82 or e88 springs but it doesn't sound like anyone's looked in to this? In terms of the front, it's likely I'll go with the Eibachs I've already got.
Haha yes it does go on abit so guess it can get confusing :oops:

My advice would be fit the Eibach pro springs you already have with new bumpstops on the original dampers if they are ok with no leaks, that said even if dampers look ok with 90k+ on they will be past there best so maybe change them at same time, its down to budget which to replace with, the Bilstein B4S for OE spec replacement and good prices, or if budget allows Koni Sport adjustables are best ive used for comfort (on softer setting) and handling (when firmed up a notch or 2)...and good balance as all rounder.

Makes sense to do dampers while doing springs/bumpstops etc especially on front as it all has to come apart might as well just do it once, rears are separate so can be done later but might as well do lot imo.

If you want lower rear (eibach pro doesn't really lower rear) then BMWP springs I used will drop it about 10mm, your sacrificing comfort though as less damper travel and they are firmer, makes it handle brilliant but little harsh for me so went back to msport springs which are goo allrounders biased towards comfort.

HTH

Ian
Cheers for the quick response. After posting the question, it dawned on me that it would probably be worth doing the bumpstops etc whilst actually changing the dampers as everything's off like you say.

I think it may be worth waiting a few months and doing the whole lot in one go and getting hold of some dampers.

I think I'd be happy to sacrifice a little comfort for handling, I've got a mate with an old s4, so need to be able to keep up with him haha in terms of the b4s dampers, did you do a track session with them? How did they perform? You've probably done a review of them already but there was so much to read and remember so forgive me!

I think bmwp rear springs sound like what I'm looking for. It's unlikely I'll have the car long enough to see the effects, but would you see increased wear from shorter springs on dampers designed for oe spec?

Cheers
Dan
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Re: My Suspension quest! 130i

Post by THETYRANT » Tue Jun 12, 2018 5:19 pm

Dan258 wrote:
Tue Jun 12, 2018 2:46 pm

Cheers for the quick response. After posting the question, it dawned on me that it would probably be worth doing the bumpstops etc whilst actually changing the dampers as everything's off like you say.

I think it may be worth waiting a few months and doing the whole lot in one go and getting hold of some dampers.

I think I'd be happy to sacrifice a little comfort for handling, I've got a mate with an old s4, so need to be able to keep up with him haha in terms of the b4s dampers, did you do a track session with them? How did they perform? You've probably done a review of them already but there was so much to read and remember so forgive me!

I think bmwp rear springs sound like what I'm looking for. It's unlikely I'll have the car long enough to see the effects, but would you see increased wear from shorter springs on dampers designed for oe spec?

Cheers
Dan
No problems glad to help if i can :)

I didnt have the B4S on for long and didnt run them on track i dont think, however i have run many track laps on bone stock Msport suspension on previous 130's and its not bad for a standard setup so the B4S will be just as good if not better, Springs are the key for track as while stock is a decent enough allrounder but if you start to push on track then firming up the springs makes a big difference to way car turns in and rolls etc espeically if fitting shorter bumpstops (stock bumpstops contribute to overall spring rates so actually quite good on track) , the BMWP springs i fitted front and rear (see a couple of pages back) gave stock front ride height and approx 5-10mm lower at rear but with approx 30% uprated spring rates, if i was doing more track i would of left them on as handling was very good, but its a rare thing these days i get on track so went back to msport for better road manners.

Wear rates wont be a problem with mild drops.

Ian
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Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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Re: My Suspension quest! 130i

Post by Dan258 » Tue Jun 12, 2018 7:01 pm

THETYRANT wrote:
Tue Jun 12, 2018 5:19 pm

No problems glad to help if i can :)

I didnt have the B4S on for long and didnt run them on track i dont think, however i have run many track laps on bone stock Msport suspension on previous 130's and its not bad for a standard setup so the B4S will be just as good if not better, Springs are the key for track as while stock is a decent enough allrounder but if you start to push on track then firming up the springs makes a big difference to way car turns in and rolls etc espeically if fitting shorter bumpstops (stock bumpstops contribute to overall spring rates so actually quite good on track) , the BMWP springs i fitted front and rear (see a couple of pages back) gave stock front ride height and approx 5-10mm lower at rear but with approx 30% uprated spring rates, if i was doing more track i would of left them on as handling was very good, but its a rare thing these days i get on track so went back to msport for better road manners.

Wear rates wont be a problem with mild drops.

Ian
This is like speaking to a suspension encyclopaedia haha thanks for your help.

I don't want to hijack the thread and ask a million questions and be that annoying person but a couple of last things.
Do I remember somewhere in the thread that the bmwp have a higher spring rate than the Eibach pros? As I understand, this effectively means a stiffer spring and therefore would likely perform better on track assuming no other changes? Would it be a noticeable difference?

Second one, I don't think you looked in to the Eibach sportlines. I've done a bit of reading and they seem to be stiffer and lower than anything you've looked in to. Did you research them at all? Others have said on an m sport it lowers the front by around 35mm and the rear by around 15-20mm. You say that damper wear rates won't be a problem for mild drops but my guess would be that this is slightly too much. My thoughts are this would be slightly excessive and with wider tyres and m3 lcas and 12mm spacers, there's a chance of rubbing on arches and tbh, I cba to deal with that haha

Thanks again,
Dan
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Re: My Suspension quest! 130i

Post by THETYRANT » Tue Jun 12, 2018 7:34 pm

Dan258 wrote:
Tue Jun 12, 2018 7:01 pm

This is like speaking to a suspension encyclopaedia haha thanks for your help.

I don't want to hijack the thread and ask a million questions and be that annoying person but a couple of last things.
Do I remember somewhere in the thread that the bmwp have a higher spring rate than the Eibach pros? As I understand, this effectively means a stiffer spring and therefore would likely perform better on track assuming no other changes? Would it be a noticeable difference?

Second one, I don't think you looked in to the Eibach sportlines. I've done a bit of reading and they seem to be stiffer and lower than anything you've looked in to. Did you research them at all? Others have said on an m sport it lowers the front by around 35mm and the rear by around 15-20mm. You say that damper wear rates won't be a problem for mild drops but my guess would be that this is slightly too much. My thoughts are this would be slightly excessive and with wider tyres and m3 lcas and 12mm spacers, there's a chance of rubbing on arches and tbh, I cba to deal with that haha

Thanks again,
Dan
LOL no just someone who has spent way to much time and money swapping suspension about :lol:

There are lots of different BMWP springs but they ones I found were highest rate fro E8x platform which was about 10% stiffer than Eibach Pro from what I remember, also i didn't want to lower car as think stock is low enough so was good front didn't drop at all but rear did a tad, not huge amount though and acceptable, biggest issues with lowering is reduce suspension free travel (before bumpstop intervention) which affects comfort and also ground clearance problems on speedbumps and ramps etc.

I did look at the Eibach Sportline kit but its way to low to give a decent ride quality imo also ground clearance is greatly reduced, another issue i don't need. To me its the Chav spring kit for those wanting slammed look but too tight to buy proper suspension to do it.

Spacers and lowering along with M3 LCA is a whole other story, i found with 12mm spacers on front and M3 LCA i had some slight scrubbing inside the arch, all depends on quality of roads you travel on though i guess, fitting camber plates to tip wheel over more can help but lots of other factors like tyres etc to take into account.

Ian
--
Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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Re: My Suspension quest! 130i

Post by Dan258 » Tue Jun 12, 2018 8:27 pm

THETYRANT wrote:
Tue Jun 12, 2018 7:34 pm

LOL no just someone who has spent way to much time and money swapping suspension about :lol:

There are lots of different BMWP springs but they ones I found were highest rate fro E8x platform which was about 10% stiffer than Eibach Pro from what I remember, also i didn't want to lower car as think stock is low enough so was good front didn't drop at all but rear did a tad, not huge amount though and acceptable, biggest issues with lowering is reduce suspension free travel (before bumpstop intervention) which affects comfort and also ground clearance problems on speedbumps and ramps etc.

I did look at the Eibach Sportline kit but its way to low to give a decent ride quality imo also ground clearance is greatly reduced, another issue i don't need. To me its the Chav spring kit for those wanting slammed look but too tight to buy proper suspension to do it.

Spacers and lowering along with M3 LCA is a whole other story, i found with 12mm spacers on front and M3 LCA i had some slight scrubbing inside the arch, all depends on quality of roads you travel on though i guess, fitting camber plates to tip wheel over more can help but lots of other factors like tyres etc to take into account.

Ian
Well I'm very grateful you've gone through all the time and effort and done the write up on it so thanks very much.

Sounds like I'll go for Eibach pro fronts and bmwp rear springs with b4s. Slightly lower with the comfort and performance balance I'm after I think.

I'll probably end up asking about how to deal with a rubbing issue eventually but for now I'll leave you to your evening!

Thanks again for your help. Genuinely great knowledge and advice.
BMW 130i e87 Black Sapphire 2008

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Re: My Suspension quest! 130i

Post by ian_h » Fri Jul 13, 2018 3:53 pm

Hi Ian, I'm about half way through reading this thread :lol: and I think I'm right in what I'm looking at for my ideal setup. So I'm on knackered m sport suspension at the moment and looking at refreshing /replacing.

I do like a sporty ride and my weekly commute involves alot of a/b roads and long motorway driving so I'm after something that will let me push on and corner hard whilst still be comfortable when I'm on the motorway and going over pot holes / speed bumps. Also I'm not wanting to lower the car.

From your recommendations I'm thinking of going with:
Bmwp bumpstops, Bilstein b4's dampers and possibly eibach Pro springs as I've read they dont lower the car much over m sport.

The main issue I. Having is getting the correct part numbers as I'm looking at larkspeeds website and im guessing it's the ones with sports suspension is what I need. Manufacturer part no. 22144270 for front right for example.

I'm getting confused with the correct options and if I should use SE bumpstops and normal m sport springs. Please help :roll:
E87 2010 120d - P-torque remap 222 bhp - BMWP exhaust - ssk - cruise control retrofit- Toby depo's

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Re: My Suspension quest! 130i

Post by THETYRANT » Fri Jul 13, 2018 4:22 pm

ian_h wrote:
Fri Jul 13, 2018 3:53 pm
Hi Ian, I'm about half way through reading this thread :lol: and I think I'm right in what I'm looking at for my ideal setup. So I'm on knackered m sport suspension at the moment and looking at refreshing /replacing.

I do like a sporty ride and my weekly commute involves alot of a/b roads and long motorway driving so I'm after something that will let me push on and corner hard whilst still be comfortable when I'm on the motorway and going over pot holes / speed bumps. Also I'm not wanting to lower the car.

From your recommendations I'm thinking of going with:
Bmwp bumpstops, Bilstein b4's dampers and possibly eibach Pro springs as I've read they dont lower the car much over m sport.

The main issue I. Having is getting the correct part numbers as I'm looking at larkspeeds website and im guessing it's the ones with sports suspension is what I need. Manufacturer part no. 22144270 for front right for example.

I'm getting confused with the correct options and if I should use SE bumpstops and normal m sport springs. Please help :roll:
If you were reasonably happy with the Msport setup then just changing the dampers to Bilstein B4S and renewing bumpstops is all you really need to do, providing of course the springs are in good shape ?

Bumpstop wise BMWP options front and rear is a safe bet, using Koni rears gives more travel and comfort but some find it a little soft due to this, i like it as rear feels well planted on mine :)

If you go for Eibach Pro springs it drops the front about 10-15mm from a good (not sagged/broken) Msport spring, on rear it often sits about 5-10mm higher with the Eibachs due to increased spring rate on the Eibach setup and often stock rears look to sit a little low. It does seem to vary a bit car to car though.

Bilstein damper wise yes the ones for Sport chassis is what you need on Msport car and that number you quoted looks correct.

HTH
--
Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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Re: My Suspension quest! 130i

Post by Trojantrow » Sun Jul 15, 2018 9:51 am

I was wondering.

I think the d1 springs on the rear (what mine has) are slightly softer than d0 springs on the pre fl car.

So. Koni bump stops.
Rear brace off a 3 door
Rear subframe inserts
D0 springs.
B4 sport dampers.

This should stop the bad ride without making it too soft.. does that sound a good idea?

Is there any other rear springs one should consider.?

I'm worried about putting eibach pro springs on the rear as I beleive the b4 damper can't control higher spring rates properly which is another reason it bounces up and down.

Highly sprung under damped.

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Re: My Suspension quest! 130i

Post by THETYRANT » Mon Jul 16, 2018 10:24 am

Trojantrow wrote:
Sun Jul 15, 2018 9:51 am
I was wondering.

I think the d1 springs on the rear (what mine has) are slightly softer than d0 springs on the pre fl car.

So. Koni bump stops.
Rear brace off a 3 door
Rear subframe inserts
D0 springs.
B4 sport dampers.

This should stop the bad ride without making it too soft.. does that sound a good idea?

Is there any other rear springs one should consider.?

I'm worried about putting eibach pro springs on the rear as I beleive the b4 damper can't control higher spring rates properly which is another reason it bounces up and down.

Highly sprung under damped.

Sent from my SM-G920F using Tapatalk
Pre-Fl cars run a firmer rear spring from what ive seen myself around 25lbs more on my first 2006 130i, i might try a set of these myself at some point in my FL car but difference is pretty minimal really.

B4S dampers are oe spec so will control any spring designed for that including the Eibach, as long as you have shorter bumpstops as its the long/hard stock bumpstop which damper struggles with not so much the coil spring.

First thing to change if current dampers/springs are in decetn state is rear bumpstops see how car feels for you, its quick and easy to do and you can just trim stock ones as experiment for free.
--
Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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Re: My Suspension quest! 130i

Post by HaiderGill » Tue Jul 31, 2018 12:22 am

Ian deserves a good pat on the back. I have been running the Koni FSDs, Koni rear bumpstops, Eibach Pros and SE front bumpstops. The rear I find spot on - compliant yet taut. The front I think I needs the firmer BMWP front bumpstops as on crest on the autobahn I feel the front bottoms out. I have to be at the airport before 0530 in the morning and what with motorways being pretty clear I channel my inner Flying Scotsman. The flip side of the coin is it is comfortable on road imperfections and doesn’t wallow about during handling/braking. I’m not sure if that is down to the frequency selective damping. I do the A507 Baldock to Buntingford run, because the corners you can see around coupled with being empty on a Sunday evenings means you can put the power down. In fact the handling has gone up to such a high level that really road speeds aren’t challenging, the car just takes it in it’s stride. I have still to put on the Powerflex rear subframe and anti-roll bar bushes on, along with M Performance front calipers - I have plans for Millbrook...
120d RS (RoadSport) Steptronic 5 door in Sparkling Graphite, Koni FSDs, Eibach Pro Kit, black leather, BMWP Style 269, PS4, Professional Sat-Nav, iPod integration kit, Bluetooth, custom speaker install, performance pedals:)

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Re: My Suspension quest! 130i

Post by THETYRANT » Tue Jul 31, 2018 7:26 am

Thanks glad your enjoying your setup :)
--
Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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My Suspension quest! 130i

Post by HaiderGill » Wed Aug 01, 2018 11:38 am

THETYRANT wrote:Thanks glad your enjoying your setup :)
How r u getting on with the Quaife? I have always toyed with the idea of getting a Quaife but 300lb-ft and 255s on the rear even with greasy roads I’m not getting the traction issues just grip just puts the power down. When the tread wears out, I’m going to try 235s. I want to get a Quaife at that point but I’m also looking to get an Evora or E89 Z4s as weekend toy to pair up with the 120d...Suprisingly the Lotus is winning on practicality and comfortImageQuieter cabin and more comfortable ride than the 987 Cayman S plus 2 small seats in the back for the kids. Then chuck in the fact that it’s a better drivers car the Cayman had no advantages. Coupled with Jap reliability on the engine, gearbox etc...is appearing like a no brainer...
120d RS (RoadSport) Steptronic 5 door in Sparkling Graphite, Koni FSDs, Eibach Pro Kit, black leather, BMWP Style 269, PS4, Professional Sat-Nav, iPod integration kit, Bluetooth, custom speaker install, performance pedals:)

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Re: My Suspension quest! 130i

Post by THETYRANT » Wed Aug 01, 2018 12:29 pm

HaiderGill wrote:
Wed Aug 01, 2018 11:38 am
THETYRANT wrote:Thanks glad your enjoying your setup :)
How r u getting on with the Quaife? I have always toyed with the idea of getting a Quaife but 300lb-ft and 255s on the rear even with greasy roads I’m not getting the traction issues just grip just puts the power down. When the tread wears out, I’m going to try 235s. I want to get a Quaife at that point but I’m also looking to get an Evora or E89 Z4s as weekend toy to pair up with the 120d...Suprisingly the Lotus is winning on practicality and comfortImageQuieter cabin and more comfortable ride than the 987 Cayman S plus 2 small seats in the back for the kids. Then chuck in the fact that it’s a better drivers car the Cayman had no advantages. Coupled with Jap reliability on the engine, gearbox etc...is appearing like a no brainer...

I havent felt the need for a Quaife in this 130i yet ( had one in last car) as with the suspension working as it should along the the E-LSD (these facelift 130's have but earlier car didnt) traction hasnt been an issues even running 225 wide PS4 rear, previously had MPSS in 245 wide on rear and they nearly killed me in the wet when rear let go big style! 245 wide MPSS have such narrow tread cuts they just couldnt clear the water but these 225 wide PS4 have no issues wet or dry so far, ive not pushed them much on track yet but balance of car feels good now with 225 front and rear and on road its perfect with the Koni dampers and bumpstops etc.

To me on the road the Quaife isnt really needed if suspension and tyres are good, if anything it makes the car more lairy which if you want that its a worthwhile mod, i found on last 130 with the Quaife you needed to be very careful on tight junctions in wet if you didnt want to pull off large drifts everytime you set off!, maybe 20years ago it would of been more appealing but these days i just like to make progress without sliding the back every opportunity, must be getting old :D
On track is where the LSD comes into its own but even then if your smooth and rest of car is working good its not as much of an issue as previous cars ive found.

Ian
--
Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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My Suspension quest! 130i

Post by HaiderGill » Thu Aug 09, 2018 5:18 pm

From what I found out is that the FSD, Eibach Pro spring and front SE Bumpstop triumverate is being highly compressed at supersonic speeds on autobahn crests. When this situation occurs the bumpstop starts messing with the frequency of the oscillation. The frequency selective damping in the FSD gets confused by this. The FSD damper is designed to progressively stiffen as it travels during the compression stroke but if the bumpstop comes into play and creates a big increase in resistance it triggers hit a pot hole mode to help the wheel deal with mid corner pot-holes when this situation occurs it goes into soft damping mode. I believe it thinks a pot-hole and the spring compresses and uncompresses too quickly causing the front of the car to feel as if it is being pushed up. So the SE bumpstop is not short enough or progressive enough in stock form to work with FSDs in these situations. I have attached a photo below of the bumpstop next to BMW Performance suspension bumpstop - not my photo. As a first stop I am going to trim the nose of the SE bumpstop so that it looks like the BMW performance bumpstop. I’m thinking the SE bumpstop has lower spring rate than the BMW Performance one. but I don't know the spring rate of the individual bumpstop parts but I am working on the logic if the BMW Performance bumpstop does not have the softer nose part and the fact it should haver a higher spring rate I should be fine. This will allow it to be confirmed if the bumpstop length is causing this issue and if free damper travel will alleviate this situation from occurring. The rear is on the Koni bumpstop and works fine.

Ian wondering why the Koni bump stop used at the rear shouldn’t be used in the front too?

120d RS (RoadSport) Steptronic 5 door in Sparkling Graphite, Koni FSDs, Eibach Pro Kit, black leather, BMWP Style 269, PS4, Professional Sat-Nav, iPod integration kit, Bluetooth, custom speaker install, performance pedals:)

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Re: My Suspension quest! 130i

Post by THETYRANT » Fri Aug 10, 2018 7:50 am

This is why I didn't get on with the FSD dampers I tried some time back, to be fair I was using them on stock msport bumpstop/springs as it was first aftermarket setup I tried on the bmw so beginning of a long learning curve, however the FSD just isn't clever enough to work on a setup like these with such limited stroke in my opinion and does what you describe.

I have briefly tried playing around with much shorter front bumpstops but without custom coil springs of much higher rate it just doesn't work, the front is very reliant on the Bumpstop to assist the coil spring to prevent car bottoming out, going too short on front bumpstop just makes front of car feel all wrong as there is not enough support to hold the car up, you probably could improve things on your car with either new Msport or BMWP bumpstops but its always a compromise due to the relatively soft coil springs for the stock damper setups, even with Eibach etc which worsens the problem due to reducing travel by being lower.

You get away with shorter bumpstops on the rear as it doesn't see the same loads as the front end of car and due to motion ratio and other parts of design has more travel range, so allowing more damper free travel improves the comfort without too many other downsides unless running car heavily loaded.

I would like to try a custom spring on front but its a lot of work/expense, while on these Koni sport dampers you can remove the lower spring platform and fit a threaded one from a company in the states which along with new tophat allows normal coilover springs to be used, its not cheap though and with such limited damper travel by design you need to run a pretty firm spring (300+lb) to support car which has impact on ride quality, on the Ohlins setup I fitted to my old 135i I tried both 342lb and 300lb front springs and 300 was about right for road but a tad too soft for track, even with a high quality damper like Ohlins there is only so much it can do with the travel available, the stock damper/bumpstop/spring goes a long way to give reasonable compromise it just struggles with bad UK roads.
--
Now on my 3rd 130i, this time a nice E81 in Graphite, Previously 2 x 130i and 2 x 135i

Camber plate project - http://www.babybmw.net/viewtopic.php?f=20&t=96465

Suspension Quest thread - http://www.babybmw.net/viewtopic.php?f=20&t=80208

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