Craig,

I checked mine today and they are installed correctly with the nut/threads down........

It's one thing to lose it because you overcooked a corner, missed an apex, or did something else becuase of fatigue (mental...not metal). At least you can study the situation and learn from your mistake. It's quite another when it's something completely out of your control.

Glad that the damage was minimal. You're a lucky man!

I think the upside down installation may have accelerated the failure. But that bolt is supposed to be working in pure tensile so it shouldn't matter which way the threads were oriented.

That 7/16 bolt is only about 11mm. That is undersized for the added leverage created by the spacer IMHO. The factory design has a much greater safety factor.

I think the bolt was loose as someone above said. But it may have become loose due to stretch (a result of undersize bolt and added leverage). Once loose it was just a matter of time till failure.

That's what I was going to say... if the bolt lost it's preload, that's when the fatigue would have been the fastest

What do you guys think about changing those bolts at half the life time experienced before the failure ?

Craig,

Have you notified ERP of this failure of one of their components?

Perhaps they would look into a redesign.

Exactly. I am working on it - I have a contact for Eisenlohr.

Not arguing here, just looking at things and asking questions...

It seems the upside down installation would be the biggest culprit. It seems the pivoting tie rod around the bolt would lessen the overall force on the bolt making it less likely to fail if installed correctly. However, the sheer forces on the top of the bolt would seem to be higher. Given the fact that a cut thread is weaker anyway, it makes sense that it fractured the way it did.

Here is the question of for the rest of us... Is the bump steer setup ultimately unsafe in the long haul, especially under high load? Or, did the reversal of the bolt cause a somewhat extreme example of a BIG oops?

Do we all go out and check our bolts for fatique/cracking? It would suck to have that happen at ANY time, much less under high load/speed situations...

I too think the upside down boof was the culprit - & the threads are mashed from the strut arm contact.

Come Monday or so I need to 'go have a chat'http://www.pelicanparts.com/support/smileys/chix.gif

Looks like I ought to replace the OTHER SIDE bolt too - it surely has been compromised. And gets higher loads at the Seattle area PRI track (many left turns)

Yes, Craig, you should replace the other one. You got lucky once - don't push it.
:)

I'd say, if the a bolt being upside down could cause the steering to fail, the design is too weak to start with.

Glad to see that you're okay and the SC is very repairable.

I noticed that you had recently gone to JRZ shocks. Was something not put back together properly after installation of the shocks?

All the best.

Richard

Craig,
Sorry about the off. Glad you're ok and not too much damage to your car.

Good luck with your "chat". :)

Craig, glad you are okay. I am interested to see how things turn out when you talk to the shop that installed them. Turn 9 is not where I would want to have problems like you had!!!! Better there than going into turn 1 I guess.

Jeff

are there any markings on the head of the bolt (like ridges from the center to one of the points)? a photo would be good.

http://www.americanfastener.com/techref/grade.htm

http://forums.pelicanparts.com/uploa...1100554125.jpg

Above is what you need to do when using very long bump-steer drop-links. This is a drop-link that has been gusseted to the steering arm, but later removed to change sizes. It shows the bracing. This keeps from introducing too much flex on the long through-bolt.

Tyson or anyone what ride height would require a bump street kit like that?

I like that, Tyson.

Here is the bolt head - nothing - no markings. Make any sense?
http://forums.pelicanparts.com/uploa...1100555023.jpg

Here is a new bump steer assy - same bolt, btw:
http://forums.pelicanparts.com/uploa...1100555102.jpg