Z4M Frame issue... If you track your car look at this thread!

[Z4-VILLA]

6^ looking foward to seeing that...

[inTgr8r]

Originally Posted by ryanchua

I had the same thing happen to me a month ago.

Was running beefed up ground control sway bars and the mount plates gave way pretty much like how it is in your post. Anyway - a guy who did racecars said it was pretty standard for street cars when they're beefed up, and furthermore, it's empty right behind where the bar bolts to the frame. That's a big weak spot - but sufficient for street ARBs.

Not to repeat what others have already said in here, but i did some frame reinforcements and now it's all welded a lot more strongly. I''ll take some photos when i get to my next servicing.

Don't worry - just beef it up more.

Thanks for jumping in on this.
Pics on your fix would be great.

A second incident confirms the need to address this for anyone tracking the car.

[Caddyshk]

Originally Posted by F360C

This is exactly what the engineers said was the cause for the failure. Thin steel that was flexing back and forth eventually led to the metal becoming weak. Not much unlike the e46 subframe failure.

My buddy who has the rally prep shop is going to be welding a plate on there for me this week. He say it should be stronger once the plate is on there then it was before the mount tore it self up.

Couldn't be the 100 or so Autocross and PDE's you've done over the past couple of years

[Serious]

Originally Posted by MIKe86

Why 1992?

Because that is when BMW began emphasizing cost over engineering integrity. It's not such a bad thing if these cars are used solely for road use, they just aren't designed to handle the constant loading & unloading the track puts on them.

[thekurgan]

Seems to me, track time and/or the stiff bars will just speed up this weak spot and that, eventually, even street cars will have the issue, just farther down the road.

[MIKe86]

Originally Posted by Serious

Because that is when BMW began emphasizing cost over engineering integrity. It's not such a bad thing if these cars are used solely for road use, they just aren't designed to handle the constant loading & unloading the track puts on them.

Posts like these that make me miss my e30.

Until I get back behind the wheel of my coupe that is...

[Beedub]

well i enjoy my car on the track with stock suspension, if i get this failure ill make it last forever with a proper fix, me....... im not even worried about it ;-)

mine look like new still ;-)

[mhughett]

I just got an email from Turner and apparently, the've seen these failures before. Seems they sell a complete kit with reinforced steel at certain key failure points. See link below.

http://www.turnermotorsport.com/c-24...=reinforcement

[Finnegan]

Originally Posted by mhughett

I just got an email from Turner and apparently, the've seen these failures before. Seems they sell a complete kit with reinforced steel at certain key failure points. See link below.

http://www.turnermotorsport.com/c-24...=reinforcement

Which components did Turner recommend? Since our front suspension is E36 derived, the E36 kit I'd guess?

If they made any specific recommendations that would be good info.

[thekurgan]

Originally Posted by Finnegan

Which components did Turner recommend? Since our front suspension is E36 derived, the E36 kit I'd guess?

If they made any specific recommendations that would be good info.

Looks like the E36, with the dual bolt holes.

[runnerx]

I am going to inspect mine this weekend (hopefully). I have been hearing pop coming (pretty certain) from the rear during hard acceleration from full stop. It isn't loose sway, I checked multiple times but I never inspected the subframe.

I would think the subframe issue is addressed on the newer models after all those E36 and E46 complaints and class action lawsuit.

Maybe it is time to sit down and put some serious thought on Z06.

[thekurgan]

Originally Posted by runnerx

I am going to inspect mine this weekend (hopefully). I have been hearing pop coming (pretty certain) from the rear during hard acceleration from full stop. It isn't loose sway, I checked multiple times but I never inspected the subframe.

I would think the subframe issue is addressed on the newer models after all those E36 and E46 complaints and class action lawsuit.

Maybe it is time to sit down and put some serious thought on Z06.

Sounds like RTAB noise from the back, have you inspected those as well?

[sipman]

Sorry to hear about the bolts pulling through. But something you wrote got my ears picked up. I still haven't installed my splitter. You're already remounting yours? Are you finding it a pain to have installed? Or something go wrong in the last install?

[ryanchua]

Hello all,

I had my servicing done today - so i can show you what happened. Took some photos but I think a video might be better to explain.

So the area behind the bolts were pretty much empty.

The guys who build race cars, decided to weld a piece of solid block piece of metal (sorry - can't recall what it was) onto the subframe, welded it all around with the same stuff they did for their race car. Then bolted the Ground Control ARBs to it.

They did the same reinforcement for the rear ARBs as they commented that the link looked very weak.

I'll be going to another track session end month and I'll do a hoist and check to see whether everything is holding up fine. The race guys assured me that it'd be strong based on their experience - so we'll see how that turns out.

[mpower03]

bump any news?