Weld-In rear shock brace

#1

I just got my car back from the cage builder (Robinson Racing) and based on some posts I’ve read, I’m wondering if I’m legal.

I have a bar welded between the rear shock towers and then the two bars from the main hoop are welded to this “cross bar”. This didn’t create any extra chassis mounting points (I have 8 total), but I’m still curious if it’s legal?

  • I hope this doesn’t turn into a cage design thread… just a rules one!

Matt

#2

doesn’t sound like it on two counts

  • spec e30 only allows a bolt-in rear strut bar
  • all “required” bars in a cage need to end at a mounting plate (not another bar) - the two rear brace bars from the main hoop are required bars. The idea is to put that joint in compression/tension, not shear.

I just ran into the same issue with a new spece30 guy in the RM region and he is now modifying the rear half of his cage.

If you asked your cage builder to build to our rules, then the onus should be on him to fix it.
sorry,
bruce

#3

Yes and no. Call me and I’ll try to explain.

Regards, Robert Patton 800-755-1715

#4

Not legal as I understand it. Here is mine

#5

Not trying to highjack, but what do you guys think of this rear strut bar.

http://cgi.ebay.com/ebaymotors/BMW-E30-318is-M3-325is-325e-Rear-Strut-Bar-Brace_W0QQcmdZViewItemQQcategoryZ33703QQihZ007QQitemZ170187069985QQtcZphoto

Kinda pricey, 184+57 S&H, plus, i am thinking i can just make one out of steel? Its not going to weigh THAT much more?

#6

Nicely built but a waste of money, IMHO.

#7

ditto, the rear shock towers only have the top of the shock absorbers there so the benefit of bracing it is nil. If you do a conversion to coilovers, then it might help.

Simon’s cross brace down near the spring load points is likely more beneficial, but even that is in diminishing-returns territory.
cheers,
bruce

#8

Yeah, I am going to build my own out of steel. 1/8" plate which will also be a upper shock mount reinforcement, and then a 1" .120 wall tube across with maybe a gusset at the tower. The only costly part will be getting the plates lasercut. I’ll post pics once i build it.

#9

…its a waste of time and effort for the return…