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Which Bilsteins for E86 with M Sport suspension option?

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ionofchios
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Which Bilsteins for E86 with M Sport suspension option?

Post by ionofchios » Tue Dec 12, 2017 6:40 pm

Sorry, this has been kind of covered in lots of other posts, but I can’t find a clear and definitive answer.

I’ve just got an E86 3.0si with M Sport suspension option. I’m going to refresh the the front suspension, but I don’t want to change the ride height. I’ve come to the conclusion that Suplex 06248 are the same spec as standard M Sport springs, and they are 270 mm. But, which Bilsteins should I go for? Again, I don’t want to change the ride height, which I believe is about 15 mm lower than standard suspension.

So, B6s or B8s, I guess - but which? Can anyone confirm that B8s will not change the ride height?

I mailed Bilstein, and they recommended B12 kit, but I think that is because I also asked them if they make springs as well, and that is the only product they do that would include springs.
Last edited by ionofchios on Tue Dec 12, 2017 7:13 pm, edited 2 times in total.

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When ch Bilsteins for E86 with M Sport suspension option

Post by philbo909 » Tue Dec 12, 2017 6:59 pm

ionofchios wrote: Tue Dec 12, 2017 6:40 pm Sorry, this has been kind of covered in lots of other posts, but I can’t find a clear and definitive answer.

I’ve just got an E86 3.0si with M Sport suspension option. I’m going to refresh the the front suspension, but I don’t want to change the ride height. I’ve come to the conclusion that Suplex 06248 are the same spec as standard M Sport springs, and they are 270 mm. But, which Bilsteins should I go for? Again, I don’t want to change the ride height, which I believe is about 15 mm lower than standard suspension.

So, B6s or B8s, I guess - but which? Can anyone confirm that B8s will not change the ride height?

I mailed Bilstein, and they recommended B12 kit, but I think that is because I also asked them if they make springs as well, and that is the only product they do that would include springs.
B4 sport is MSport equivalent (same height, as firm)
B6 is upgrade (same height, firmer)
B8 is upgrade (lower height, firmer)

B4 and suplex springs shouldn't cost more than £400

I reccomend b4s and and suplex, they're what I changed to a few months ago.
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Which Bilsteins for E86 with M Sport suspension option?

Post by Scooba_Steve » Tue Dec 12, 2017 7:14 pm

A shock doesn't change ride height.

If you don't want to lower then B4 will be fine
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Which Bilsteins for E86 with M Sport suspension option?

Post by ionofchios » Tue Dec 12, 2017 7:26 pm

Thanks guys.

Ah, yes, I understand that struts don’t change the height, per se, though I suppose if they were way too short, they would compress the spring, right? Anyways, maybe the question is which shock would work best with this spring, lengthwise?

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Which Bilsteins for E86 with M Sport suspension option?

Post by ionofchios » Tue Dec 12, 2017 7:29 pm

philbo909 wrote: Tue Dec 12, 2017 6:59 pm
ionofchios wrote: Tue Dec 12, 2017 6:40 pm Sorry, this has been kind of covered in lots of other posts, but I can’t find a clear and definitive answer.

I’ve just got an E86 3.0si with M Sport suspension option. I’m going to refresh the the front suspension, but I don’t want to change the ride height. I’ve come to the conclusion that Suplex 06248 are the same spec as standard M Sport springs, and they are 270 mm. But, which Bilsteins should I go for? Again, I don’t want to change the ride height, which I believe is about 15 mm lower than standard suspension.

So, B6s or B8s, I guess - but which? Can anyone confirm that B8s will not change the ride height?

I mailed Bilstein, and they recommended B12 kit, but I think that is because I also asked them if they make springs as well, and that is the only product they do that would include springs.
B4 sport is MSport equivalent (same height, as firm)
B6 is upgrade (same height, firmer)
B8 is upgrade (lower height, firmer)

B4 and suplex springs shouldn't cost more than £400

I reccomend b4s and and suplex, they're what I changed to a few months ago.
Philbo, did you use the same Suplex spring that I listed, 06248? You have M Sport suspension, right?

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Which Bilsteins for E86 with M Sport suspension option?

Post by davros » Tue Dec 12, 2017 8:15 pm

I believe the B8 strut is designed for shorter springs and these are the struts Bilstein include with eibach springs in their B12 kit.
As others have said, the B4 & B6 are for standard height springs, with the B6 being slightly firmer.
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Which Bilsteins for E86 with M Sport suspension option?

Post by philbo909 » Tue Dec 12, 2017 11:07 pm

ionofchios wrote: Tue Dec 12, 2017 7:29 pm

Philbo, did you use the same Suplex spring that I listed, 06248? You have M Sport suspension, right?
I have SE spec springs and shocks, my old Zed was MSport and I didn't like the firmness.
I can't remember which codes the springs were, like you I struggled to find information, so just email an eBay seller and they will confirm
http://vi.raptor.ebaydesc.com/ws/eBayIS ... spheader=1
edit:
SE codes are 06252 front spring, 06228 rear spring
so not those, but probably 06248 as the only suspension options are sport and se
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Which Bilsteins for E86 with M Sport suspension option?

Post by ionofchios » Wed Dec 13, 2017 7:34 am

Thanks, all, for your input! It helps.

So, some summary points:
  • B4 and B6 are for standard springs
  • B8 is for lowered springs
  • B6 and B8 are the same firmness
  • B4 is less firm that B6 and B8
  • Bilstein’s view is that M Sport suspension option is a lowered spring (even though only 15 mm), so recommend the B8
  • there are several reports of people using B4 and B6 with M Sport setup and not having any problems
  • there are several reports of people using B8 with M Sport setup, also not having issues - the B8 is not ‘too short’ for the only slightly lowered M Sport spring (15 mm), even though it can handle much greater lowering (30-40 mm)
  • Bilstein are inconsistent with recommendations regards B4: sometimes say they are for standard, non-lowered setups, and sometimes for lowered setups, up to 40 mm Eibach (from MACK)
  • B6 and B8 are 10-20% stiffer than B4 (from MACK)
  • B4 is somewhat equivalent to OEM M Sport struts regards stiffness (from MACK)
So, in short, if I stick with M Sport springs, I could use any of these struts and it would work fine. Therefore, I think I will go with B8s, since that is the Bilstein recommendation, and I can find them a bit cheaper.

If anyone finds any fallacy somewhere in my statements or reasoning, please let me know;)

Part numbers
Suplex M Sport equivalent front spring: 06248 (270 mm)
Bilstein B8 front left: 35-124122
Bilsteins B8 front right: 35-124115
Last edited by ionofchios on Wed Dec 13, 2017 10:09 am, edited 5 times in total.

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Which Bilsteins for E86 with M Sport suspension option?

Post by MACK » Wed Dec 13, 2017 8:02 am

ionofchios wrote: Wed Dec 13, 2017 7:34 am Thanks, all, for your input! It helps.

So, some summary points:

B4 and B6 for standard springs
B8 is for lowered springs
B6 and B8 are the same firmness
B4 is less firm that B6 and B8
Bilstein’s view is that M Sport suspension option is a lowered spring (even though only 15 mm), so recommend the B8
There are several reports of people using B4 and B6 with M Sport setup and not having any problems
There are several reports of people using B8 with M Sport setup, also not having issues - the B8 is not ‘too short’ for the only slightly lowered M Sport spring (15 mm), even though it can handle much greater lowering (30-40 mm)

So, in short, if I stick with M Sport springs, I could use any of these struts and it would work fine. Therefore, I think I will go with B8s, since that is the Bilstein recommendation, and I can find them a bit cheaper.

If anyone finds any fallacy somewhere in my statements or reasoning, please let me know;)

Part numbers
Suplex M Sport equivalent front spring: 06248 (270 mm)
Bilstein B8 front left: 35-124122
Bilsteins B8 front right: 35-124115
The only thing I would add to the above is to highlight the contridictory nature of the bilstein advice regarding the B4 shocks. On one hand they tell you they're for standard, so non M Sport suspension. Only then to tell you they're fine for use with lowering springs up to 40mm. My understanding is if comfort rather than performance is your primary driver then using B4 shocks instead of B6/8 is the way to go. The B6/8 stuff is 10-20% uprated over an already stiff M Sport shock. Where the B4 is supposidly akin to the non M Sport shock. Yes utimately the monotube B6/8 will out perform the twin tube B4 but plenty have paired the B4 with both M Sport and Eibach springs and like it. Especially over knackered original shocks for standard road use.
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Which Bilsteins for E86 with M Sport suspension option?

Post by ionofchios » Wed Dec 13, 2017 10:12 am

MACK wrote: Wed Dec 13, 2017 8:02 am
ionofchios wrote: Wed Dec 13, 2017 7:34 am Thanks, all, for your input! It helps.

So, some summary points:

B4 and B6 for standard springs
B8 is for lowered springs
B6 and B8 are the same firmness
B4 is less firm that B6 and B8
Bilstein’s view is that M Sport suspension option is a lowered spring (even though only 15 mm), so recommend the B8
There are several reports of people using B4 and B6 with M Sport setup and not having any problems
There are several reports of people using B8 with M Sport setup, also not having issues - the B8 is not ‘too short’ for the only slightly lowered M Sport spring (15 mm), even though it can handle much greater lowering (30-40 mm)

So, in short, if I stick with M Sport springs, I could use any of these struts and it would work fine. Therefore, I think I will go with B8s, since that is the Bilstein recommendation, and I can find them a bit cheaper.

If anyone finds any fallacy somewhere in my statements or reasoning, please let me know;)

Part numbers
Suplex M Sport equivalent front spring: 06248 (270 mm)
Bilstein B8 front left: 35-124122
Bilsteins B8 front right: 35-124115
The only thing I would add to the above is to highlight the contridictory nature of the bilstein advice regarding the B4 shocks. On one hand they tell you they're for standard, so non M Sport suspension. Only then to tell you they're fine for use with lowering springs up to 40mm. My understanding is if comfort rather than performance is your primary driver then using B4 shocks instead of B6/8 is the way to go. The B6/8 stuff is 10-20% uprated over an already stiff M Sport shock. Where the B4 is supposidly akin to the non M Sport shock. Yes utimately the monotube B6/8 will out perform the twin tube B4 but plenty have paired the B4 with both M Sport and Eibach springs and like it. Especially over knackered original shocks for standard road use.
Thanks! I have added your input to the original list.

Damn, now I'm thinking I will cancel buy order and go for B4s with the same Suplex springs :D

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Which Bilsteins for E86 with M Sport suspension option?

Post by philbo909 » Wed Dec 13, 2017 10:48 am

ionofchios wrote: Wed Dec 13, 2017 10:12 am
MACK wrote: Wed Dec 13, 2017 8:02 am
ionofchios wrote: Wed Dec 13, 2017 7:34 am Thanks, all, for your input! It helps.

So, some summary points:

B4 and B6 for standard springs
B8 is for lowered springs
B6 and B8 are the same firmness
B4 is less firm that B6 and B8
Bilstein’s view is that M Sport suspension option is a lowered spring (even though only 15 mm), so recommend the B8
There are several reports of people using B4 and B6 with M Sport setup and not having any problems
There are several reports of people using B8 with M Sport setup, also not having issues - the B8 is not ‘too short’ for the only slightly lowered M Sport spring (15 mm), even though it can handle much greater lowering (30-40 mm)

So, in short, if I stick with M Sport springs, I could use any of these struts and it would work fine. Therefore, I think I will go with B8s, since that is the Bilstein recommendation, and I can find them a bit cheaper.

If anyone finds any fallacy somewhere in my statements or reasoning, please let me know;)

Part numbers
Suplex M Sport equivalent front spring: 06248 (270 mm)
Bilstein B8 front left: 35-124122
Bilsteins B8 front right: 35-124115
The only thing I would add to the above is to highlight the contridictory nature of the bilstein advice regarding the B4 shocks. On one hand they tell you they're for standard, so non M Sport suspension. Only then to tell you they're fine for use with lowering springs up to 40mm. My understanding is if comfort rather than performance is your primary driver then using B4 shocks instead of B6/8 is the way to go. The B6/8 stuff is 10-20% uprated over an already stiff M Sport shock. Where the B4 is supposidly akin to the non M Sport shock. Yes utimately the monotube B6/8 will out perform the twin tube B4 but plenty have paired the B4 with both M Sport and Eibach springs and like it. Especially over knackered original shocks for standard road use.
Thanks! I have added your input to the original list.

Damn, now I'm thinking I will cancel buy order and go for B4s with the same Suplex springs :D
Just to add confusion, you have standard bilstein b4 and sport bilstein b4
SE and MSport equivalent
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Which Bilsteins for E86 with M Sport suspension option?

Post by ph001 » Wed Dec 13, 2017 11:01 am

Does the shock really make a big difference to the ‘hardness’ of the suspension anyway? Obviously it controls compression and rebound dsmping but I would have though the hardness is primarily down to the stiffness of the spring.
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Which Bilsteins for E86 with M Sport suspension option?

Post by ionofchios » Wed Dec 13, 2017 11:16 am

ph001 wrote: Wed Dec 13, 2017 11:01 am Does the shock really make a big difference to the ‘hardness’ of the suspension anyway? Obviously it controls compression and rebound dsmping but I would have though the hardness is primarily down to the stiffness of the spring.
I guess the more it damps, the more it stops the spring compressing as fast as it otherwise would, so it will be 'harder'.

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Which Bilsteins for E86 with M Sport suspension option?

Post by Chris1981 » Wed Dec 13, 2017 1:32 pm

ionofchios wrote: Wed Dec 13, 2017 11:16 am
ph001 wrote: Wed Dec 13, 2017 11:01 am Does the shock really make a big difference to the ‘hardness’ of the suspension anyway? Obviously it controls compression and rebound dsmping but I would have though the hardness is primarily down to the stiffness of the spring.
I guess the more it damps, the more it stops the spring compressing as fast as it otherwise would, so it will be 'harder'.
When i went from OEM to B8's the ride firmed up significantly... although my OEMs were 90k miles old and completely shot!

I believe you've come to this conclusion yourself already but if you have M Sport you need the B8's, image below is front B6 and OEM M Sport, I made the mistake of ordering B6s as I read they are fine to replace M Sport and cheaper than the B8's while offering the same damping rate... but I didn't feel comfortable fitting something so different and the supplier was kind enough to do a straight swap to the B8s!
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Which Bilsteins for E86 with M Sport suspension option?

Post by MACK » Wed Dec 13, 2017 2:22 pm

philbo909 wrote: Wed Dec 13, 2017 10:48 am
ionofchios wrote: Wed Dec 13, 2017 10:12 am
MACK wrote: Wed Dec 13, 2017 8:02 am

The only thing I would add to the above is to highlight the contridictory nature of the bilstein advice regarding the B4 shocks. On one hand they tell you they're for standard, so non M Sport suspension. Only then to tell you they're fine for use with lowering springs up to 40mm. My understanding is if comfort rather than performance is your primary driver then using B4 shocks instead of B6/8 is the way to go. The B6/8 stuff is 10-20% uprated over an already stiff M Sport shock. Where the B4 is supposidly akin to the non M Sport shock. Yes utimately the monotube B6/8 will out perform the twin tube B4 but plenty have paired the B4 with both M Sport and Eibach springs and like it. Especially over knackered original shocks for standard road use.
Thanks! I have added your input to the original list.

Damn, now I'm thinking I will cancel buy order and go for B4s with the same Suplex springs :D
Just to add confusion, you have standard bilstein b4 and sport bilstein b4
SE and MSport equivalent
They do for some models. But on the e85/6 Its just the one B4 variety which is supposedly the non m sport equivalent.
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