[rothwem]

This car has B6's on it with sport package springs, I installed them before I even knew about the difference. It bumped the car up about a half inch, but then again, that might've been the new strut mounts.

[Ninpo1]

Originally Posted by gjm120

In this thread (and others) it's been mentioned that the longer damper will raise ride height. Maybe this is simplistic, but, I don't understand how a damper that I can compress with my hands will overcome the weight of the car and effectively increase the spring height.

Am I missing something?

I don't understand how the dampers could raise the car, either. I called a supplier of Bilstein and they said that I could use either the B6 or B8's on my 328i spoert package car with OEM Sport Springs. They did say that if you replaced other wearable components that the ride height might have returned to what it was when it was when the car was newer.

[gjm120]

Originally Posted by gjm120

In this thread (and others) it's been mentioned that the longer damper will raise ride height. Maybe this is simplistic, but, I don't understand how a damper that I can compress with my hands will overcome the weight of the car and effectively increase the spring height.

Am I missing something?

Should add my question is based on the assumption that the housings and shaft length on the B6 and B8 are the same. I saw this somewhere on a side by side comparison. This assumption may be wrong therefore there will be a difference in resultant ride height.

[tlow98]

Originally Posted by gjm120

In this thread (and others) it's been mentioned that the longer damper will raise ride height. Maybe this is simplistic, but, I don't understand how a damper that I can compress with my hands will overcome the weight of the car and effectively increase the spring height.

Am I missing something?

Which struts are you compressing with your hands? Just so we can get some clarification.

They raise your car bc the static nitrogen pressure within them is very high. Think about the amount of force it takes to push the shock down. Let's say that force is 100lbs per damper. This force is effectively the same as if you pulled up on your car's fender with 100lb of force. Multiply this by 4 and it's as if your car was "unburdened" by 400 pounds, which would raise the height all things being equal.

These bilsteins do settle, but will likely be slightly higher than a comparable, low pressure twin tube damper like a Koni.

[Mikibmwsm]

Originally Posted by Ninpo1

I don't understand how the dampers could raise the car, either. I called a supplier of Bilstein and they said that I could use either the B6 or B8's on my 328i spoert package car with OEM Sport Springs. They did say that if you replaced other wearable components that the ride height might have returned to what it was when it was when the car was newer.

Car is sitting on dampers when you have lower spring than standard oem. M suspension is 15mm lower than standard. Must go with b8 or car will be sitting on dampers and it will be stiffer or maybe higher. B6 on m suspension will be too much preloaded and compresed. You will have 70% expand space and 30% max compresion space

[Spitfire007]

B6 with Sport package springs is a bit rough at slow speeds.
But take those same roads at 60 or 80, and you understand why they works so well on the nordschleife

[steifan]

For future reference:

Here is a Bilstein B8 Sprint 24-120425 compared to an early M sport rear damper BMW 33528036026 / Sachs 814903001543 :


The B8 is slightly shorter than the original shock.

[B---WLF]

I want to install Bilstein B6 damper on my BMW E92 320d xdrive automatic 2011.
In the same time, i want to lower it just a little bit (2cm front, 1cm rear). Current gap is around 4cm front and 3cm rear.

Xdrive E92s are higher with 1cm vs reardrive E92; simplest solution would be to install M paket springs with B8 (or Bilstein B12 kit), but it is not available for xdrive (it seems there is no m sport suspension installed on e92 xdrive, either).

So i am thinking to improvise a little bit: to install standard springs (actually Eibach standard springs) + bilstein B6, but those codes suited for 320d automatic reardrive, not codes for 320d xdrive automatic.

codes are the following:
Bilstein B6 front left:
320d, 330d: 35-120377
320xd, 330xd: 35-142454

Bilstein B6 front right:
320d, 330d: 35-120384
320xd, 330xd: 35-142461

Bilstein B6 rear: 24-120395, same code for all 320d/320xd/330d/330xd

So what do you think? probably front spring from 320d reardrive will be compressed with further 0.5-1cm, and the damper will stay a little bit compressed.

[cristiano07]

I am upgrading my suspension for a 2007 BMW 335i E93 N54. I have a few questions I would like to know the technical responses to. I am looking for M-sport springs but finding conflicting responses everywhere regarding this subject.
Compatibility Questions:
Are the Bilstein B3 #37-161255 springs compatible with B8 struts?
Are the Bilstein B3 #37-161255 springs sport or non-sport on a hardtop E93 convertible?
Are M-sport springs more compatible with B8 struts, Why or Why Not?

Functionality Questions:
M sport springs + B6 = more strain on the B6?
M Sport Springs + B8 = more strain on the springs?

It's hilarious that this confusion still persists after a decade. Thanks to the "RTFM"-guy I returned by B6s to FCP for B8s now I just need to confirm which springs are best suited for the B8s. I got off the phone with Bilstein's rep earlier today and he said the above-mentioned B3 heavy-duty "may" and "might" be better suited because it's a hardtop with added weight.

[cristiano07]

Originally Posted by techwhiz

That is not correct and runs counter to Bilstein's application guide. You can stand firm but you are wrong. Read the guide from the people that manufactured the parts. The M-Sport suspension has a shorter spring and a different shock than standard suspension.

From the Bilstein Application Guide Page 104.
2011-2007 B6 (HD)
Front Left 35-120377
Front Right 35-120384
Rear Suspension 24-120395
Excludes M-Technics Sport Suspension


2011-2007 B8 (SP)
Front Left 35-120407
Front Right 35-120414
Rear Suspension 24-120425
With M-Technics Sport Suspension

From the Bilstein description of the B8 - "High-performance shock absorbers and struts designed specifically for lowering springs and production sport vehicles".

Have you ever seen a sport packaged car right next to a non-sport packaged car. The ride height is almost an inch lower.

If you use the B6, the shock will be pre-loaded and have less travel than the B8. This will affect the suspension performance and ride.

The B8 is the correct replacement for Sport suspension.
Any other information is flawed because it runs counter to Bilstein - RTFM!

The B6 is a standard HD replacement.
For OE the B4 lists two separate part numbers for standard and sport suspension.

Do not put B6 shocks on a M-Technic/Sport Packaged vehicle. It is not the correct part.

As mentioned in my previous post above, I returned my B6 for B8s thanks to you. Just curious if you still stand by what you said. Also, I got off the phone with one of Bilstein's rep today and they seemed unsure about their B3 heavy-duty coil as being M-sport. He mentioned the other variations specified as "non-sport" but he thinks this particular one is potentially suitable.

Are the Bilstein B3 #37-161255 springs sport or non-sport on a hardtop E93 convertible?

I want to swap all 4 springs but cant find an affordable set other than OEM Genuine.