Help: M technic suspension?

[NeverEnough02]

Lets bump this up. When I search part numbers for replacement MT2 dampers, I get Bilstien, Sachs, and BMW as OEM for the front and Sachs for OEM rear. The prices are all over the place.

Has anyone confirmed what manufacturer originally made these for BMW to put in these cars? Mine are likely original (89k miles) and they are black unlike the yellow ones pictured earlier in this thread.

[jeffnhiscars]

i cant remember where ive seen what. i just remember looking through all the specs when i was shopping for shocks. i basically came the the result m tech was different internally. not size wise in anyway.

as both bilstien and koni list the vert/ m3 shocks as the same as m tech for sedan and coupe versions. it basically came down to a valve and rebound difference i think.

Bilstein usually valves their dampers for 4cyl cars differently than for 6's but if the PN's are the same then the internals will be. You can get the damping rates from:

Wes Welch
Technical Product Information Coordinator
Wes.Welch@thyssenkrupp.com

[e30leigh]

i cant remember where ive seen what. i just remember looking through all the specs when i was shopping for shocks. i basically came the the result m tech was different internally. not size wise in anyway.

as both bilstien and koni list the vert/ m3 shocks as the same as m tech for sedan and coupe versions. it basically came down to a valve and rebound difference i think.

[reelizmpro]

I'm sure the length/travel is the same. The m tech suspension wasn't dramatically lower than stock. The shocks were gas charged though.

[P.Kelly]

the length and diameter is the same as non m-tech shocks from what i can find? so buying a koni sport or bilstien hd or sport should be just as good or better then a factory m-tech shock? not to mention they are cheeper and servicable.

I'm trying confirm that the length/travel is the same. Where did you find this information?

[e30leigh]

what is the drama?

isnt the only difference with the m-tech shocks the internal valves and rebounding ect due the difference in spring rates and requirement for a sportier ride?

the length and diameter is the same as non m-tech shocks from what i can find? so buying a koni sport or bilstien hd or sport should be just as good or better then a factory m-tech shock? not to mention they are cheeper and servicable.

[jeffnhiscars]

I have a theory behind what has been happening since this came up before. People noticed that M3 front springs now have the same PN as 85 318i/325e springs and conclude that they have always been identical springs. This isn't true. All of those springs are different from each other. If you put M3 springs on those cars it'll lower them by about an inch. If you put 325 springs on a 318, it'll raise the 318 so high it'll look lifted, etc. What I believe is happening, is that BMW has consolidated the various springs into a single part (probably the M3 spring). So if you want to buy new springs for your 318i for some reason, you will probably get the M3 spring. I've noticed this with other BMW parts as well. If there is more than 1 version, they will supercede/consolidate them all down to one version. Then you get the part and are surprised to see that it is different but works. Examples are S14 throttle body gaskets and accelerator cables, etc. So it's not that RealOEM is wrong, it's just that BMW superceded/consolidated a lot of parts. I can't imagine them getting a lot of orders for BMW M technic rear shocks for an almost 30 year old car for $200 each when you can get the equivalent Boge Turbo Gas (or whatever they call it these days) shock for $58 each.

This ties in with my discovery that M3 Cabrio springs (euro only) are the same PN as a 318iC. I assume this is due to the similar weight of the 4 cyl engines.

I was under the assumption that boge/sachs were made by the same company.

Boge & Sachs are both ZF subsidiaries...as is Lemfoerder

[P.Kelly]

Reel - that could very well be the case. However, in other places BMW will simply discontinue the part, so I guess they maybe simply be inconsistent on how they deal with this stuff.

Have you found a suitable replacement strut/shock for an m-tech that has similar properties to the original?

[E30_Pare]

I was under the assumption that boge/sachs were made by the same company.

[reelizmpro]

I have a theory behind what has been happening since this came up before. People noticed that M3 front springs now have the same PN as 85 318i/325e springs and conclude that they have always been identical springs. This isn't true. All of those springs are different from each other. If you put M3 springs on those cars it'll lower them by about an inch. If you put 325 springs on a 318, it'll raise the 318 so high it'll look lifted, etc. What I believe is happening, is that BMW has consolidated the various springs into a single part (probably the M3 spring). So if you want to buy new springs for your 318i for some reason, you will probably get the M3 spring. I've noticed this with other BMW parts as well. If there is more than 1 version, they will supercede/consolidate them all down to one version. Then you get the part and are surprised to see that it is different but works. Examples are S14 throttle body gaskets and accelerator cables, etc. So it's not that RealOEM is wrong, it's just that BMW superceded/consolidated a lot of parts. I can't imagine them getting a lot of orders for BMW M technic rear shocks for an almost 30 year old car for $200 each when you can get the equivalent Boge Turbo Gas (or whatever they call it these days) shock for $58 each.

[P.Kelly]

This confuses me as we only got M Tech cabrio's here in the US. If you have a 91 M Technic (FULL), then you should have the m technic suspension with shocks as well.

Do you have conflicting part number for the M-Technic suspension?

If you look up the parts for the M-Technic (S771A) suspension most of the parts are cobbled together from other E30s. From what I can tell the only unique part if the front bump stop. The rest is from a 318iC or an M3, unless the BMW parts catalog is wrong (very possible).

I haven't yet taken mine apart to refresh it to confirm what is actually on the car.

[reelizmpro]

Found this:



Which appears to confirm that shocks on the m-tech are the same as on the convertible, with different bump stops and a different rear sway bar. I'll see when I pull mine apart.

This confuses me as we only got M Tech cabrio's here in the US. If you have a 91 M Technic (FULL), then you should have the m technic suspension with shocks as well.

[P.Kelly]

I take it u have a 91-92 318iC? Please let us know what u find out.

No, I have a 1991 M-Technic (S771A).

[reelizmpro]

I take it u have a 91-92 318iC? Please let us know what u find out.

[P.Kelly]

Found this:

You were looking for suspension part numbers for the convertible M-tech suspension.. From what I can tell, there's not a great deal of difference between the normal convertible suspension and the m-tech suspension.

On the front:
struts - 31321133560 (also used on 318iC?)
springs - 31331131333 (on some non-AC US E30s and lots of Euros)
absorber (bumpstop) - 31331133513

On the rear:
shocks - 33521132123 (also used on 318iC?)
rear stabilizer bar (14.5mm) - 33551129194 (also used on E30 M3)
stabilizer bar bushings - 33551130349 (also used on E30 M3)

For the struts and shocks, there are two entries under the 318iC, one that is the normal one and one that says "only applies to M technic" - both entries have the same part numbers. That's why I put the question mark beside the 318iC. As far as I can tell, everything else is the same (suspension wise).

Keith
www.e30ic.com

Which appears to confirm that shocks on the m-tech are the same as on the convertible, with different bump stops and a different rear sway bar. I'll see when I pull mine apart.