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Suspension bush options for e87 130i?

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Keen to hear recommendations ahead of replacing worn dampers and suspension bushes on the 130i. 

After initial research, I’m leaning towards Bilstein B4 dampers. But what about bushes, bump stops, &c.? Do aftermarket brands such as Superpro offer handling and ride quality benefits over OEM items, or are they false economy for road use? Finally, what other parts should be checked/replaced at the same time? FYI, a new set of Michelin Pilot Sport 4 (stock sizes) will be fitted too.

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It depends on what you are after. I have superpro bushes in mine, the full kit, everything is a PU bush. I think its fine for road use, and it did wonders for tightening up the suspension (even on 35 profile 19" tyres). However I have friends who think its was to harsh for a road car. 

If you do want to go PU bushes, Superpros design and quality are way above anything else Ive seen.

Bumpstops - OEM unless your shock kit includes them. The rear shock mounts (top and bottom) are also wear items, and again, OEM is the best bet. There are also a number of spherical bushes in the ass end suspension, which are often the first to go, replace them with OEM. 

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38 minutes ago, Jacko said:

It depends on what you are after. I have superpro bushes in mine, the full kit, everything is a PU bush. I think its fine for road use, and it did wonders for tightening up the suspension (even on 35 profile 19" tyres). However I have friends who think its was to harsh for a road car. 

If you do want to go PU bushes, Superpros design and quality are way above anything else Ive seen.

Bumpstops - OEM unless your shock kit includes them. The rear shock mounts (top and bottom) are also wear items, and again, OEM is the best bet. There are also a number of spherical bushes in the ass end suspension, which are often the first to go, replace them with OEM. 

I'm after predictable town and open road handling and ride quality—general driving. Thanks for the endorsement of Superpro bushes. From your description, a combination of Superpro bushes, and OEM bumpstops and rear shock mounts sounds OK. Didn't understand basis for OEM rear spherical bushes... why not Superpro? And front ARB bushes?

Edited by PRC

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13 minutes ago, PRC said:

I'm after predictable town and open road handling and ride quality—general driving. Thanks for the endorsement of Superpro bushes. From your description, a combination of Superpro bushes, and OEM bumpstops and rear shock mounts sounds OK. Didn't understand basis for OEM rear spherical bushes... why not Superpro? And front ARB bushes?

PU bushes replace rubber bushes that are designed to move primarily in one axis, some of the suspension joints do more than one axis, so you cant replace spherical bush with a PU one. 

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Thank you, appreciate the lesson.

Edited by E30 325i Rag-Top
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Yes SuperPro are very good, have no hesitation in using them. If you're going to use BMW bump stops you MUST use BMW Performance ones, they're shorter, the stock ones are downright dangerous as your shocks wear.

Read this and pop back to ask questions: https://www.babybmw.net/viewtopic.php?f=20&t=80208

  

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On the shocks question, My 330 is on the bilstein B4 kit, its essentially the same as OEM in the E91.. I dont know if the valving is different to the Msport E87 setup or not in the B4 E87 config.. if it isnt Id try something else personally as the stock Msport suspension isnt very nice on NZ roads, its overly sprung and crashy, and it likes to skip across bumps etc on your average NZ B road. 

I cant really say whats the best option, due to not having tried them all, however I have the birds custom valved B12 kit and really rate it when combined with birds spec eibach springs. I think you'd struggle to find anything better matched to NZ B roads, its probably too soft for the track though. 

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53 minutes ago, Jacko said:

On the shocks question, My 330 is on the bilstein B4 kit, its essentially the same as OEM in the E91.. I dont know if the valving is different to the Msport E87 setup or not in the B4 E87 config.. if it isnt Id try something else personally as the stock Msport suspension isnt very nice on NZ roads, its overly sprung and crashy, and it likes to skip across bumps etc on your average NZ B road. 

 

I think you will find it's the Bilsteins that are crashy  and not the spring rate , Bilstein run much higher compression damping and lower rebound damping than the stock or a Koni OE replacement/ sports upgrade. 

The bilsteins fitted to my X5 exhibited exactly this characteristic - Had them shock dyno'd which proved it - We then used the rates out of a range rover of similar vintage to recalibrate them ( because there were no published rates for the X5 and the rear suspension geometry is similar).  

Essentially compression damping was reduced to 30% of original value and rebound increase 250% of original now th e X5  doesn't crash or skip  and its on the same wheels, tyres and springs. 

I wouldn't recommend Bilstein in any road car with stiffer springs  - every experience I have had with them has been unrewarding 

Edited by 3pedals
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Stock Msport shocks on E87s are sachs, which are just crashy, the Birds/Eibach/Bilsteins are softer springs than stock but have stiffer swaybars. Its a hard supension is "sporty" thing that BMW do :D 

https://www.birdsauto.com/product-information/b1-dynamics-package-upgrade-bmw-e87-130i-and-e82-135i

 

Edited by Jacko

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Yep , got the Sachs in my E87 , they are fine  but tired which is why the bump stops are demolished. 

The Birds stuff is just marketing bollocks and note where the tests are done - a flat race track 

The E87 runs a soft rear sway bar like 99% of the cars on the road to introduce understeer as the chassis gets pushed - the motorsport upgrades in most BMWs is a bigger rear bar - this brings the chassis balance closer to neutral. 

The reason for running an open diff is also to reduce turn-in understeer - like 99% of the rear drive cars on the road.

The soft spring hard compression as per your comment is exactly what I commented on - that IS the problem:  the spring isn't supporting the car ,the stiff compression is that causes the chatter (skipping) and then it slams into the bump stop -  this gives the classic chatter (skipping) / crash/ boing chracteristic - if you don't want it don't use that combo 

Fortunately Koni do shocks for the E87 so they will be going in at some stage  

 

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How is getting custom valved shocks and spring rates developed by a suspension engineer/works driver marketing bollocks? Proof is in the pudding, and its good pudding :D 

Read some more, the BMWCar mag article is a good one. It was developed for the road, hence why most dont like it on the track as the spring rates are too low.

Id place money on BMW not putting LSDs in em to be more down to cost cutting than anything.  

 

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Used B4's on a few BMW's and a Mercedes with stock springs, similar performance and ride to the sport dampeners they replaced. Good option if you can get them cheaper than Sachs.

I wouldn't bother with PU bushings in your case, more hassle\cost than it's worth for a average road car. They need to be re-lubed and rarely worth the improvement over fresh rubber. Ive had good life out of Meyle HD arms\bushings.  

Yeah the B6 and B8's ive had needed to or were re-valved (like most decent suspension packages seem to do)

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2 hours ago, M3AN said:

Yes SuperPro are very good, have no hesitation in using them. If you're going to use BMW bump stops you MUST use BMW Performance ones, they're shorter, the stock ones are downright dangerous as your shocks wear.

Read this and pop back to ask questions: https://www.babybmw.net/viewtopic.php?f=20&t=80208

  

Thanks. I found this thread earlier this morning and will read it later. 

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What's marketing bollocks: - the bits I commented on (i.e - not the commentary on the shock consultant) 

Read the full "The Tyrant'  monologue - he covers it well.  The key is the end point he comes to: Correctly adjusted Koni sports, with sport springs and the correct bump stops. Its the whole package not the 3/4 package he did the first time.  Nice find  @M3an

In regard to the OP re: Urethane :

Good in the front end to improve precision in steering,   good in rear trailing arms, okay in the rear  and in sub frames - mainly because doing a bush replacement with OE bushes is a bastard of a task and you need a monty press for the subframe ones - whereas the Urethanes don't.  

My cars are littered with Powerflex Urethane  bushes found them to be good except the front transverse ones on the X5 - they creak/move  after a while and the alignment goes out so gone back to standard ones. 

 

 

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What makes it slightly more confusing is there is a B1 V1 and B1 V2, mines the V2 with the thinner rear swaybar and higher spring rates (still much larger rear sway, and lower rates, than stock). Be really curious to see what the difference is back to back with the V1 (which is what the Tyrant ran), it sounds like Birds/Harvey Bailey took the community feedback from the V1 and tweaked em. 

 

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Unless they totally reversed the shock charcteristics they won't be able to make them work with the stock spring rate so they would have to go to softer springs and this then leads to more roll bar to regain the roll stiffness. 

The higher spring rate in the V2 gives better (more) pitch and roll control so the compliment to this is to ease the roll bar  to maintain roll characteristic - all completely normal in terms of suspension development, the roll bar can still be quite  a bit stiffer than stock because the stock one is there for Joe average.  

The guys at Autolign were reluctant to do the change to the B6's in my X5 but once they did and drove the car they accepted it was exactly what the problem was - It is more a B6 & B8 issue  but B4's do have a bias as well. 

Stiffer springs, less compression damping and softer roll bar provides a little more axle articulation/ and less weight transfer  leading to an improvement in traction for a small trade off in rear roll stiffness. The trick is to balance this with the front end to maintain neutral handling. 

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Just read through various comments (and thanks to contributors). How do Koni FSD and Sport (adjustable?) compare with Bilstein B4 then?

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13 minutes ago, PRC said:

Just read through various comments (and thanks to contributors). How do Koni FSD and Sport (adjustable?) compare with Bilstein B4 then?

I don't think we can answer any more of your questions until you've posted pictures and details of your car. 😁

 

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I've had:

One set of FSD and the build quality was average

5 sets of Sport adjustables , current ones have been rebuilt twice and have done 250,000km 

2 sets of Bilsteins, first set were rebuilt 5 times in 3 months second set have done 90,000 km with a rebuild after suffering the original valving for 40,000 k 

My ranking of based on the above 

  1. Koni S.A  out of the box - 9/10 
  2. Bilstein out of the box 2/10 
  3. Bilstein re-valved - 9/10 
  4. Koni FSD  out of the box 5/10 

Look at tthe graph below  and spot one obvious error - the rebound on the Koni should start at '0' that aside what you see is the Bilstein is much stiffer in initial compression - results in chatter and harsh ride but its also really soft in initial rebound  compare that to the soft compressin on the Koni and imediate control of rebound 

 

 

BilsteinvsKoniSA.jpg

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I'm not sure on the science but there's a lot of support out there for the Birds setup. I have no doubt that it's far superior to stock and would work well for most street applications. All said and done it's their full kit with LSD that makes them shine, I'd skip the ARB's if your skipping the LSD.

 

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14 minutes ago, M3AN said:

I'm not sure on the science but there's a lot of support out there for the Birds setup. I have no doubt that it's far superior to stock and would work well for most street applications. All said and done it's their full kit with LSD that makes them shine, I'd skip the ARB's if your skipping the LSD.

 

Faulty logic in that @M3an -   The LSD masks the stiffness of the rear end all you need to do is run the right mix of spring rate , compression control and roll control and it's fine 

So if you are going to bother doing the shocks and some bushes definitely do the bar as well  but don't go silly 30 to 40% stiffer is all you should do on an open diff.

And the advantage of the Sport adjustables is you can dial in some roll stiffness with the rebound control - more holds the inside wheel up - like a stiffer roll bar  but without the same level of weight transfer. 

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36 minutes ago, M3AN said:

I don't think we can answer any more of your questions until you've posted pictures and details of your car. 😁

 

Our current BMW is a 2006 130i; New Zealand-new, with full BMW dealer service history (excepting one WOF).

  • Colour: Le Mans Blue
  • Interior: 'Boston' black leather
  • Options: S704, S339, S337, S710, S715, S441, S470, S473, S430, S431, S481, S411, S494, S459, S493, S4MG, S644, S609, S620, S540, S548, S534, S520, S502, S508, S522, S2MG, S249, S874, S775, S925, S9AA, S864, S853, S818, S302, S321, S825, S880
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8 minutes ago, 3pedals said:

Faulty logic in that @M3an -   The LSD masks the stiffness of the rear end all you need to do is run the right mix of spring rate , compression control and roll control and it's fine 

So if you are going to bother doing the shocks and some bushes definitely do the bar as well  but don't go silly 30 to 40% stiffer is all you should do on an open diff.

And the advantage of the Sport adjustables is you can dial in some roll stiffness with the rebound control - more holds the inside wheel up - like a stiffer roll bar  but without the same level of weight transfer. 

Okay, 30 to 40% is fine, yes. But that's still nothing, 15mm or so, and I would just skip it.

My comment was in relation to the Birds ARB which is much thicker and therefore only suitable with a LSD. 

Edited by M3AN

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32 minutes ago, PRC said:

Our current BMW is a 2006 130i; New Zealand-new, with full BMW dealer service history (excepting one WOF).

  • Colour: Le Mans Blue
  • Interior: 'Boston' black leather
  • Options: S704, S339, S337, S710, S715, S441, S470, S473, S430, S431, S481, S411, S494, S459, S493, S4MG, S644, S609, S620, S540, S548, S534, S520, S502, S508, S522, S2MG, S249, S874, S775, S925, S9AA, S864, S853, S818, S302, S321, S825, S880

Pics and VIN, or doesnt exist :D There are only 13 of em, so spotters will be googling furiously for this info in 20 years. 

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52 minutes ago, M3AN said:

Okay, 30 to 40% is fine, yes. But that's still nothing, 15mm or so, and I would just skip it.

My comment was in relation to the Birds ARB which is much thicker and therefore only suitable with a LSD. 

Yep 15mm sounds about right , will work nicely with stock or sport springs with similar rate to make the most of the limited articulation range - combined roll stiffness will be fine and traction will be fine. 

The Bird bar size is required to compensate for the lack of spring derived roll stiffness, however this makes  the rear end behave more like a live axle as there is far less 'independance of wheel movement - all covered  previously. 

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