Z4M Roadster - best affordable strut brace

[mRoadster06]

Anyone have experience with the various options and know which is the least expensive strut brace that will actually make a difference?

I’m a bit surprised how expensive they are for the M Roadster (z4) compared to every other sports car I’ve installed these on, and even compared to the non-M z4.

Thanks!

[pungo]

From what I've read, the E85/E86 platform is pretty stiff to begin with and unless you're running super sticky rubber and or suspension mods, a strut brace will have a negligible effect on handling, unlike many other platforms with more flex at the towers. My Z4MC came with a OEM strut brace, though I've driven the same vehicle without a brace and couldn't tell a difference in spirited driving, maybe it'll make more of a difference on a modded Z4MR

I read a M3 brace will fit with a simple mod.

[mRoadster06]

Thanks! This is my engine bay … is this the OEM brace you’re referring to? Or is there an OEM one that goes straight across?

[pungo]

Originally Posted by mRoadster06

Thanks! This is my engine bay … is this the OEM brace you’re referring to? Or is there an OEM one that goes straight across?

Those are often called firewall strut braces, standard on all E85/E86 vehicles.
Yes, the optional OEM strut brace goes straight across.

[Auelox]

Strong Strut has announced that they have a few strut braces available. https://www.strong-strut.com/?syclid...6-f95acd41e0d3

[belcom]

I am running an e46 M3 strut bar. They pop up all the time. Fits great, does the job.

[Huz-Z]

Originally Posted by belcom

I am running an e46 M3 strut bar. They pop up all the time. Fits great, does the job.

They fit a 3.0si too?

[belcom]

Originally Posted by Huz-Z

They fit a 3.0si too?

I have the M3 bar on my M Coupe. On the Si I have Strong Strut. So not sure.

The strut towers are the same between the two. Its the height of the engine that is different. N52 vs S54. I never tried to fit the M3 bar on the Si. I am sure someone tried already just have to find that info.

[Huz-Z]

Thanks!

If the Z4M engine sits higher than an N52 then perhaps the M3 bar will also fit an SI.

[mRoadster06]

Originally Posted by belcom

I am running an e46 M3 strut bar. They pop up all the time. Fits great, does the job.

Any modification needed to fit it? And are the bolts single use?

[belcom]

Originally Posted by mRoadster06

Any modification needed to fit it? And are the bolts single use?

No modifications. Just need the strut bar and special nuts to attach.

This type of nut:
https://www.rogueengineering.com/Rog...241_p_358.html

These are titanium replacements for original PN# 51-71-7-895-241

And whatever you do, do not over-tighten these. You'll brake the studs if you do.

[mRoadster06]

Thanks! Do you know if aftermarket options for e46 fit on m roadster? And do the aftermarket ones generally include the replacement nuts? Thanks!

[belcom]

Originally Posted by mRoadster06

Thanks! Do you know if aftermarket options for e46 fit on m roadster? And do the aftermarket ones generally include the replacement nuts? Thanks!

Technically should but research and ask the manufacturers before buying anything. No idea about the hardware. You have to ask them as well. But I think the original BMW e46 m3 strut brace is the best option. It fits, its light and does the job.

I personally noticed that my regular Z4 3.0si roadster has become more responsive and a little bit more stable at higher speeds in the front after strut brace went in. But I don't think it made a huge or noticeable difference on the M Coupe because chassis is twice as stiff on the coupe already. M Roadster/Coupe also has different suspension geometry so it might have a completely different feel compared to a regular Z4. Your alignment settings and wheels/tires will also play a role in how the car feels in different driving scenarios. What's your goal with this car?

I'd say this. If you're not tracking the car there's practically no point getting a strut brace. The car is already good for street/canyon carving. Its probably the most affordable way to go about it. Get an alignment done and ask them to do the best they can for your driving style.

Aftermarket support is there but sort of limited to a few options because there are not that many of these around and frankly these cars are almost 20 years old as well. Its not your common honda, mazda, subaru etc.