Z4M Front Sway Bar Ripped From Frame

Z///Ms · 06-18-2012, 11:33 PM

Thought I would share. So when you upgrade to PSS10 coil overs and GroundControl sway bars and track the car for 30+ events, and the front sway bar bracket rips the two mounting studs from the frame, I would suggest you call Bavarian Specialties (610) 277-6037 (near Philidelphia). They did a great job coming up with a repair/reinforcement. And it gave the sway bar a little clearance from the oil pan as the bar rubs the pan alittle under track loads. The car is ready for the next track event; Watkins Glen.

ZStig · 06-19-2012, 12:20 AM

oh wow, good to know

007MCoupe · 06-19-2012, 12:58 AM

Story on how you managed that one?

beta · 06-19-2012, 02:19 AM

This is the second report of this failure. First thread here.

Tonybest · 06-19-2012, 05:10 AM

Quote:

Originally Posted by Z///Ms

... The car is ready for the next track event; Watkins Glen.

When are you going? I'll be there next Monday and Tuesday. Would be nice to meet you.

F360C · 06-19-2012, 07:13 AM

Yep this happened to me also... cross my fingers but since I had it welded it has not cracked again. There was also a guy in Singapore that had this happen to him so this now makes 3 people total.

seank · 06-19-2012, 04:44 PM

Not good. Thanks for the info. I wonder if it has more to do with it hitting the oil pan. I will look into mine.

007MCoupe · 06-19-2012, 05:38 PM

Well, I've got a new item for my checklist when I get her back.

Thanks!

seank · 06-19-2012, 05:51 PM

What spring rate are you running in the front? Just curious if it has to do with running a very stiff bar with soft springs.

F360C · 06-19-2012, 06:08 PM

Quote:

Originally Posted by seank

What spring rate are you running in the front? Just curious if it has to do with running a very stiff bar with soft springs.

I am running 600lbs fronts and 750lbs rears

EMP07 · 06-19-2012, 08:26 PM

Quote:

Originally Posted by F360C

I am running 600lbs fronts and 750lbs rears

That is a stiff one you got there sir

Z///Ms · 06-19-2012, 09:42 PM

Quote:

Originally Posted by 007MCoupe

Story on how you managed that one?

It was not a specific event that caused it to happen, (nothing off track).
I belive it's the cycling that fatigues the subframe and causes the failure.

It happened at NJMS Lighting. After a couple sessions the car started to oversteer a bit. I thought it was the tires heat cycling out as they were near the end of life. During my inspection getting ready for the next track event, I found the right side of the sway bar hanging down and studs pulled out of the frame.

Kgolf31 · 06-19-2012, 09:46 PM

This is now what I want to hear

Z///Ms · 06-19-2012, 09:49 PM

Quote:

Originally Posted by Tonybest

When are you going? I'll be there next Monday and Tuesday. Would be nice to meet you.

I'll be at Watkins July 11 & 12. Delaware Valley BMW CCA school. Sorry I'll miss you. Any chance you will be at Calabogie July 21-22?

Z///Ms · 06-19-2012, 10:01 PM

Quote:

Originally Posted by seank

What spring rate are you running in the front? Just curious if it has to do with running a very stiff bar with soft springs.

600lb springs. The car is set up very nice for the track. I'm an Instructor so the car is run hard on the track. It's has seen a little over 2 seasons of track events (about 57 track days) with the upgraded suspension.

Tonybest · 06-19-2012, 10:41 PM

Quote:

Originally Posted by Z///Ms

I'll be at Watkins July 11 & 12. Delaware Valley BMW CCA school. Sorry I'll miss you. Any chance you will be at Calabogie July 21-22?

YES! see you there

AUTOX08MC · 06-21-2012, 07:54 AM

Mine also did this after one season of about 20 autocrosses....solution was reinforced mounting points...cost about $200 in labor from a good fabricator/welder...it will not come off again

inTgr8r · 06-21-2012, 09:09 AM

looks like a trend.

upshot is if you plan to go to a bigger front bar, you should reinforce the mounting block at the same time.

Jumbosock · 06-21-2012, 12:35 PM

Did all the occurrences happen with the upgraded swaybars? Anyone have this happen on stock sways?

The HACK · 06-21-2012, 12:59 PM

NORMAL.

This happens to quite a few E36es and E46es that are tracked regularly that I know of, especially with upgraded suspension and/or upgraded sway bars. More common with cars that run sticky tires like R-Comps.

Beedub · 06-28-2012, 07:43 AM

i think upgrade roll bars are just to much for the area to handle, you must, repeat must beat these mount mounts if you plan to use upgraded ARBs, id like the Gc units but would want these heavily re-inforced if i went that route, i dont think you wiull encounter this problem with the stock ARBs which are imo thick enough for track duty, the tuning for me needs to be in the suspension.....

JasonH · 06-28-2012, 09:21 AM

Are there any kinds of bolt-on reinforcements or are they all weld-on?

06-18-2012, 11:33 PM	#1
Z///Ms New Member 6 Rep 22 Posts Drives: Z3M Rstr, Z3M Coupe, Z4M Coupe Join Date: Jul 2010 Location: PA iTrader: (0)	Z4M Front Sway Bar Ripped From Frame Thought I would share. So when you upgrade to PSS10 coil overs and GroundControl sway bars and track the car for 30+ events, and the front sway bar bracket rips the two mounting studs from the frame, I would suggest you call Bavarian Specialties (610) 277-6037 (near Philidelphia). They did a great job coming up with a repair/reinforcement. And it gave the sway bar a little clearance from the oil pan as the bar rubs the pan alittle under track loads. The car is ready for the next track event; Watkins Glen. Attached Images
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06-19-2012, 12:20 AM	#2
ZStig instagram 997turbotom 279 Rep 7,376 Posts Drives: Interlagos Z4MR Join Date: Jun 2008 Location: Delray Beach, FL iTrader: (4)	oh wow, good to know __________________
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06-19-2012, 12:58 AM	#3
007MCoupe Lieutenant Colonel 92 Rep 1,546 Posts Drives: '18 Sakhir M3 ZCP Join Date: Jun 2010 Location: ( ///// ) iTrader: (5)	Story on how you managed that one? __________________ Become a ///Member!
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06-19-2012, 02:19 AM	#4
beta Lieutenant Colonel 80 Rep 1,663 Posts Drives: 2006 M Roadster Join Date: Mar 2011 Location: CA iTrader: (2)	This is the second report of this failure. First thread here. __________________ modification journal
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06-19-2012, 07:13 AM	#6
F360C Major 366 Rep 1,373 Posts Drives: E86 S54 Join Date: Apr 2006 Location: Hoboken, NJ iTrader: (2)	Yep this happened to me also... cross my fingers but since I had it welded it has not cracked again. There was also a guy in Singapore that had this happen to him so this now makes 3 people total. __________________ 07 Z4 M Coupe AW/IR
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06-19-2012, 04:44 PM	#7
seank enthusiast 48 Rep 1,695 Posts Drives: e30 m3,e90 wagon,sprinter,z4m Join Date: Dec 2011 Location: sacramento, ca iTrader: (4)	Not good. Thanks for the info. I wonder if it has more to do with it hitting the oil pan. I will look into mine.
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06-19-2012, 05:38 PM	#8
007MCoupe Lieutenant Colonel 92 Rep 1,546 Posts Drives: '18 Sakhir M3 ZCP Join Date: Jun 2010 Location: ( ///// ) iTrader: (5)	Well, I've got a new item for my checklist when I get her back. Thanks! __________________ Become a ///Member!
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06-19-2012, 05:51 PM	#9
seank enthusiast 48 Rep 1,695 Posts Drives: e30 m3,e90 wagon,sprinter,z4m Join Date: Dec 2011 Location: sacramento, ca iTrader: (4)	What spring rate are you running in the front? Just curious if it has to do with running a very stiff bar with soft springs.
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06-19-2012, 09:46 PM	#13
Kgolf31 Brigadier General 459 Rep 4,531 Posts Drives: 2007 Z4MC, 2012 128i Join Date: Sep 2008 Location: Ohio iTrader: (4)	This is now what I want to hear
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06-21-2012, 07:54 AM	#17
AUTOX08MC Private 3 Rep 51 Posts Drives: 16 M4 Join Date: May 2011 Location: Indianapolis iTrader: (1)	Mine also did this after one season of about 20 autocrosses....solution was reinforced mounting points...cost about $200 in labor from a good fabricator/welder...it will not come off again __________________ 2016 BMW M4 MW 6SPD,2005 Honda S2000 2014 Subaru STI (Sold),2008 BMW Z4 MC (Sold) 2012 VW GTI (Sold),2006 Subaru STI (Sold) 2003 Subaru WRX (Sold),1996 Mustang Cobra (Sold) 1986 Dodge Shelby Charger (Sold)
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06-21-2012, 09:09 AM	#18
inTgr8r Lieutenant General 2426 Rep 11,667 Posts Drives: M2 Comp Join Date: Mar 2006 Location: Toronto iTrader: (10)	looks like a trend. upshot is if you plan to go to a bigger front bar, you should reinforce the mounting block at the same time. __________________ '21 M2C Hockenheim Silver '18 718 Cayman S Lava Orange (sold) '13 E92 M3 Santorini Blue (sold) '07 Z4 M Coupe Alpine White (sold)
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06-21-2012, 12:35 PM	#19
Jumbosock Captain 76 Rep 987 Posts Drives: 2007 M coupe Join Date: Apr 2011 Location: San Diego iTrader: (0)	Did all the occurrences happen with the upgraded swaybars? Anyone have this happen on stock sways?
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06-21-2012, 12:59 PM	#20
The HACK Midlife Crises Racing Silent but Deadly Class 1820 Rep 5,337 Posts Drives: 2006 MZ4C, 2021 Tesla Model 3 Join Date: Oct 2007 Location: Welcome to Jamaica have a nice day iTrader: (1)	NORMAL. This happens to quite a few E36es and E46es that are tracked regularly that I know of, especially with upgraded suspension and/or upgraded sway bars. More common with cars that run sticky tires like R-Comps. __________________ Sitting on a beat-up office chair in front of a 5 year old computer in a basement floor, sipping on stale coffee watching a bunch of meaningless numbers scrolling aimlessly on a dimly lit 19” monitor.
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06-28-2012, 07:43 AM	#21
Beedub Major General 423 Rep 5,327 Posts Drives: 2007 Z4 M roadster vt2-500 Join Date: Sep 2007 Location: UK iTrader: (0)	i think upgrade roll bars are just to much for the area to handle, you must, repeat must beat these mount mounts if you plan to use upgraded ARBs, id like the Gc units but would want these heavily re-inforced if i went that route, i dont think you wiull encounter this problem with the stock ARBs which are imo thick enough for track duty, the tuning for me needs to be in the suspension..... __________________ Z4MR VT2 - Clubsport build. Multi award winning Detailing \| Wrap \| PPF specialists UK based - www.topwrapz.com
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06-28-2012, 09:21 AM	#22
JasonH Private First Class 2 Rep 102 Posts Drives: 2007 M Coupe, 2003 M3 Vert Join Date: May 2012 Location: Newark, DE iTrader: (1)	Are there any kinds of bolt-on reinforcements or are they all weld-on?
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