E46 M3 Suspension on Z4 3.0i

[ferrarix99]

Can anyone give me a reason it wont work? I just put pss10's on my M3 and my friend needs new suspension badly, everything is identical on the z4 to 330's and m3's. I may have to remove the stock m3 stut tower because they add caster but other than that has anyone done it?

[The__J__Factor]

Dont think suspension is interchangeable between Zs and E46s.

[ferrarix99]

i know the part numbers arent the same. I think this is just dampening differences not acutal fitment.

[Incompatible]

Originally Posted by The__J__Factor

Dont think suspension is interchangeable between Zs and E46s.

X2.
Here is a response posted by The HACK a while ago to a similar question.
"Z4 non-M sports suspension is based on the E46 non-M design. Struts, springs, shocks, control arms...etc are all interchangeable between them. The Z4 M suspension is a hybrid between E36 M3 and E46 M3, with the front suspension parts being re-designed E36 M3 parts, and the rear suspension parts being redesigned E46 M3 parts. The swaybars are from E46 M3 as well (rears are E46 M3 CSL bars).

As for comparison, the non-M Z4 will hold its own, but the MZ4s have stiffer springs and higher damper rates, plus the MZ4s have more camber up front. The lower control arm is from the E46 330i with Performance Package (ZHP). The major difference will be the fact that the MZ4 has a tuned limited slip differential while the Z4 3.0Si has an open diff, and the M has servotronic rack-and-pinion steering instead of the non-M's electronically assisted rack-and-pinion steering. The M also has a quicker steering ratio.

End result, is that on the track the M has a much higher threshold, with quicker turn-in feel. But you will not be disappointed with the 3.0Si coupe, it'll likely hang at most tracks with the best of them. 265HP on a 2,9xx lbs frame is going to make a very capable car on track."

[jojodivo]

I did a swap of a Z4M rear suspension on to a 3.0i but used the subframe off of an E46 M3 as the Z4m's was slightly damaged during shipping. The two parts were identical but I am not too sure about the front. One other thing you will have to check is the length of the drive shaft from the M3 to the Z4 (if you are changing that too), I am pretty sure the M3 has a longer drive shaft.

[ferrarix99]

im not swapping the subframe just the shocks and springs, i think im gonna try it. ill let you know how it goes

[jojodivo]

G/L with the swap let us know how it turns out

[Chris04Z4]

id like to know as well! please post a followup

[nickpapa]

Originally Posted by ferrarix99

i know the part numbers arent the same. I think this is just dampening differences not acutal fitment.

you might be right in this regard since we know for sure the E46 non-m and z4 non-m shocks are interchangable. so basically, if you know for sure that M3 shocks will work on the E46 non-m, then they will def work on the Z4.

[M-Power M3]

Did we ever find out if z4 non M suspension is interchangeable with e46 M3? I'm thinking about getting back into an M3 and would love to use my Airrex bags on it.

Came across this by a google search so there might be a more recent thread.

[Pollo809]

Are there any updates on this?
I want to make sure they are interchangeable so that I can buy e46 coilovers, since they have a bigger after market than the z4.

[Westersund]

They will fit, but they are not right for the car. The strut will be longer (thus increase ride height) and the strut/spring is tuned for a heavier car (E46). It's the same with E36's and Z3's.

[///Avi]

Are Z4M and Z4 3.0 coilovers interchangeable?

Are just lowering Springs interchangeable?

Are just damper’s interchangeable?

The second hand market seems to think these are interchangeable and I can’t really find the information anywhere.

[Westersund]

Coilovers and dampers are not interchangeable, Z4 non-M use an E46 upright while the M use a E36 style upright. Very different type of mounting. The springs however could be interchangeable but it depends upon the dimensions of the springs perches.

[///Avi]

Originally Posted by Westersund

Coilovers and dampers are not interchangeable, Z4 non-M use an E46 upright while the M use a E36 style upright. Very different type of mounting. The springs however could be interchangeable but it depends upon the dimensions of the springs perches.

Thank you for the reply.

I am looking at BC racing, ISC and K-sport coilover options for my Z4M but it seems the latter 2 don’t have options for the M.

Is it a possibility to build a kit that fits from 2 different sets. Front from an E36 M and rear from an E46 M? Not saying it’s smart. Just wondering what’s possible.

I’m beginning to understand why people don’t always love the Z4 Ms. It seems the aftermarket isn’t totally invested in such a small community. Prices seem high.

[86Zed]

Just buy the kit built for the platform, there are plenty to choose from budget to extreme. BC Racing, Bilstein, Ground Control, H&R, JRZ, KW, MCS, TC Kline, and likely more I am missing.

It is my opinion that half of these are already shared parts bin setups between the E36M/E46M as there is little market to merit fine tuning for the Z platforms.

[///Avi]

Originally Posted by 86Zed

Just buy the kit built for the platform, there are plenty to choose from budget to extreme. BC Racing, Bilstein, Ground Control, H&R, JRZ, KW, MCS, TC Kline, and likely more I am missing.

It is my opinion that half of these are already shared parts bin setups between the E36M/E46M as there is little market to merit fine tuning for the Z platforms.

I tend to agree with the “shared parts bin” comment. I just wanted confirmation from guys with a bit more knowledge on the topic.

I’ve looked into 2nd hand options and now I’m looking at new and what’s possible in the bang for buck department. Researching BC racing. There is a supplier who brings them into South Africa. KW would be awesome but at the current exchange rate I would have to save up and wait.

[Westersund]

If you like KW but think they are too pricey you can always look as ST Suspensions, KW built (internals) but without the stainless steel outside. But I'm guessing rust isn't really a problem i SA.

[///Avi]

Originally Posted by Westersund

If you like KW but think they are too pricey you can always look as ST Suspensions, KW built (internals) but without the stainless steel outside. But I'm guessing rust isn't really a problem i SA.

Rust isn’t really a concern in Johannesburg. I’ll have a look there as well.

Thank you.