I have installed 15mm spacer kits from H&R and Whiteline caster bushing, after that I went for a track day to a very tight track. First 1hr was great, the car oversteered controlably but after than ride became frustrating. The driver side rear swaybar (progress adjustable one) bushing bracket broke in half and resulted in inoperational rear swaybar. This caused the car to oversteer and loose front end traction, and for me to become very frustrated.

What do you think can cause the failure, did anyone experience that before?
The rear swaybar was set on full stiff, agx's (Front set on 4 and rear on 7) with RM springs. This was on my VE NX.

Any comments are welcomed.

We've broken lots of suspension pieces on the race cars, front and rear. They've welded up fine. Something has to give, and these cars are no longer new.

Where exactly is your point of failure? I'm not familiar with the Whiteline pieces. Can you post pics?

It was a stock bracket that broke in half as seen here:

http://i93.photobucket.com/albums/l56/wojtekj/October2009043.jpg

http://i93.photobucket.com/albums/l56/wojtekj/October2009042.jpg

The whiteline bushings were installed in the front along with the spacers which probably put more stress on the rear sway bar, possibly overloading that bracket (but I do not see the reason why it would just brake off like that). Any suggestions?

Well, you could use less sticky tires ;)

I'm willing to bet, after seeing the pictures that it's just plain old metal fatigue. I'd replace the bracket and count me surprised if it happens again.

Well, you could use less sticky tires ;)

I'm willing to bet, after seeing the pictures that it's just plain old metal fatigue. I'd replace the bracket and count me surprised if it happens again.

Can't get less sticky than 2 year old (10 track days), over-heat cycled Azenis RT-615. I am afraid to think what the NT01 which I will run next season are going to do to the NX!
Now I just gotta find a spare bracket from someone (already contacted Alex).

Thanks.

Check along the crack and look for rust. If there is rust there then it was already cracked for a while. This may have been caused by a binding sway bar bushing that allowed a twisting moment to be put into the bracket. It may also have been caused by the sway bar link being off vertical and translating some of the vertical force to horizontal. My bet is you will find rust along the crack meaning that it was partially cracked to start with. I doubt you could get enough force to just pull the metal apart like that if it was in good condition to start with. On the other hand this part was designed for a MUCH smaller diameter sway bar.

I doubt you could get enough force to just pull the metal apart like that if it was in good condition to start with.

Bob snapped the lower control arm immediately below the sway bar in this picture. I still think metal fatigue combined with high cornering forces can account for it.

And yep, I think Alex still has a parts car sitting in his driveway (last time I was there, anyway).

[QUOTE=spnx;2478689]Bob snapped the lower control arm immediately below the sway bar in this picture. I still think metal fatigue combined with high cornering forces can account for it.QUOTE]

If the bar is hitting on the lower control arm it could cause a failure of the arm. Still think that the mount had had a crack in it for a while. That would be actually be metal fatigue.

We've broken lots of suspension pieces on the race cars, front and rear. They've welded up fine. Something has to give, and these cars are no longer new.

Where exactly is your point of failure? I'm not familiar with the Whiteline pieces. Can you post pics?

do sway bars really offer the same handling characteristics/benefits when broken and welded back together though?


EDIT: oh oh.. just the bracket.. nevermind..

Thanks for all your suggestions, there were few things contributing to this failure:

1. The sway bar link on the d/s was off vertical as obewan guessed tranferring some of the horizontal forces towards the bracket (bracket designed maintly to deal with vertical forces).
2. I had to modify (grind down) the edge of the bracket when I installed the bar as there was interference between the bar and the bracket edge, weakening the bracket and allow it to bend under horizontal forces from #1.
3. The bracket is too wimpy for other-than-stock swaybars.

Since I could not easily get my hands on the used bracket, I decided to weld it up and reinforce it, making it Progress-bar-worthy. I will post the "Monster Bracket" pictures later today.
Thanks for all your help.

2. I had to modify (grind down) the edge of the bracket when I installed the bar as there was interference between the bar and the bracket edge, weakening the bracket and allow it to bend under horizontal forces from #1.
.

UUHHH, I did not notice until you said this, you put the sway bar on the wrong side of the bracket.

The drivers side bracket has the sway bar mounted on the front side of it. The passenger side bracket has the sway bar mounted on the rear side. Yes, they are opposite, don't ask me why, but Nissan designed it that way. No grinding required.

Your sway bar was probably not perpendicular to the centerline of the car. Who knows what kind of force it was putting on the bracket. I have two B-13s with the same setup on them (one is a race car). And I have not had an issue with a broken bracket.

You are right, I totally missed that it was on the wrong side of the bracket. That would cause all sorts of stress issues as the bar would be cocked in the car. It may have been binding the links or hitting the control arm which would put a lot more stress on the bracket. Plus cutting it to fit may have caused a stress riser and helped it to fail.

Grrrrrr, those Nissan engineers! It was totally my fault then! No wonder that it failed, now I know why I did not notice much difference after installing progress swaybar (it probably didn't work as well as it should).

Well, lesson learned! If I knew that on the weekend I would've modified my new braket differently, now it is going to add about 3/16" to the offset of the driver side swaybar - do you think that is going to cause an issue?

Here are the pictures of the "monster bracket":

http://i93.photobucket.com/albums/l56/wojtekj/bracket1.jpg
http://i93.photobucket.com/albums/l56/wojtekj/bracket2.jpg

Well, it will be closer than having the sway bar mounted on the wrong side of the bracket. Next time you are in a junk yard, you can pick up a new bracket for cheap!

As shared by others, I'd probably find one in a junk yard. NXPartsource probably has one too.
I've had that loosen off on me before but it's not a part that I've broken. As you keep working on that machine you're going to have one awesome track car! Keep it up!

As shared by others, I'd probably find one in a junk yard. NXPartsource probably has one too.
I've had that loosen off on me before but it's not a part that I've broken. As you keep working on that machine you're going to have one awesome track car! Keep it up!

Thank you, the bracket did well in this last weekend's Shannonville although I found out how tail happy my NX can be with rear bar set on stiffest (progress), and what the limitations of AGX/RM suspension is and my old'n'bold azenis. I was suprised at the fact that my NX did a continuous 90 minute session without a cooldown (although my brakes were a little warped from last Mosport event), I didn't realize it was that long until I saw my fuel gauge showing "E".

Well next season will bring some new upgrades including racing brake pads, oil cooler, B15 tranny, Nt01 on 15x7, roll bar and possibly a better suspension.

I'll keep you posted.