Functional Shock Tower Reinforcement?

[snakeraper11b]

I've almost got my 01 all back together suspension wise (Full MM front end, STB, MM CO's front and rear FTBR full rear and MM spherical rear shock mounts. The car won't be a DD anymore, just a weekend warrior for canyons, so I'm concerned about the structural integrity of the rear shock towers with solid mounted CO's when exposed to surface street dips, bumps, pot-hotels, all that jazz. Has anyone come up with a functional rear shock tower brace that takes into account the vertical loads? I saw a pic long ago where a guy with a similar set up, but without the spherical mounts, managed to separate this shock tower from the chassis while driving! I'd very much like to avoid that. Also, adding a cage that ties into the rear shock towers is not an option right now. I'll be officially importing the car to Canada this year and I'm sure a cage won't fly at the border. Thanks for your opinions and insight.

 

[03 DSG Snake]

I've seen only the braces that tie horizontally across the towers like Hans or Steeda, or the Kenny Brown brace which attaches to the trunk floor, which is supposedly rather weak.

 

[snakeraper11b]

I've seen only the braces that tie horizontally across the towers like Hans or Steeda, or the Kenny Brown brace which attaches to the trunk floor, which is supposedly rather weak.

Yeah, those are exactly what I don't want. The Kenny Brown piece is laughable at best. The angle it's trying to brace the towers from and the direction the forces are being exerted into it make it's usually incredibly strong triangular shape almost pointless.

I've been tinkering with the idea of making something similar to this out of cardboard, then having a local metal shop cut the real ones from 5/16" mild steel plate and welding them in with a mig.

I think 2 plates on top to the right and left of the mount, tying the tower to the tub, then 2 plates paralleling the tub line, perpendicular to the tower tying it into the floor. Below is a pic of my current set up for visualization purposes. Any opinions on that idea?

 

[xtreme_exploder]

I was planning on seam welding all around the tower after scraping away that sealer bead you see in your picture. I imagine that would more than suffice. Your plate idea would only help even more.

 

[99COBRA2881]

+1

Scrape the seam sealer off the shock towers and seam weld them. The rear subframe runs just in board of the shock tower so there is some value in tying the shock tower together better.

Reseal them cause you can see daylight when the sealer is removed.

I don't think the worry is justified considering the number of race cars that are using the stock shock towers without issue.

 

[snakeraper11b]

+1

Scrape the seam sealer off the shock towers and seam weld them. The rear subframe runs just in board of the shock tower so there is some value in tying the shock tower together better.

Reseal them cause you can see daylight when the sealer is removed.

I don't think the worry is justified considering the number of race cars that are using the stock shock towers without issue.

I'll probably just do that. However, the key thing you pointed out is many racecars don't have issues. I feel like surface streets will be much more harsh. Although, driving hard on the apexes is probably harsh too.

 

[99COBRA2881]

Curbing on a race track is much worse than anything I've encountered on the street!

 

[iismet]

Back when I purchased my Cobra, I also purchased a book by William Mathis on improving Mustang performance. He showed DIY stuff including a shock tower brace. I purchased something from a vendor, but it was just ridiculous so I looked at the Mathis book and fabbed my own. I did not follow him exactly, but we bent up some L shapes and welded them to the tower and the floor. Then we welded some tube between the L shapes.

The Mathis brackets they used to sell (still do?) for solving the cantilever bracket on the IRS we installed and welded a tube between them just as we had done for the tower brace. We then stitch welded a shear plate to the parallel tubes.

The suggestion of scraping sealer and seam welding is a good one. When my car was new it made strange noises in the rear. When I installed the tower brace I pulled the sealant and the passenger side well and it was not fully welded. We welded it all up and noise was gone.

We have MM3 struts,shocks, & springs sitting on the bench. I plan to pull the sealant out of the other side and make sure both sides are fully seam welded.

A shock tower brace is an easy thing to fab, Now that I am tracking the car I would not consider running without one.

chr

 

[03 DSG Snake]

Any pics of all this deliciousness issmet?

 

[03 DSG Snake]

Any pics of all this deliciousness issmet?

 

[iismet]

Delicious - no - LOL!
Functional - yes

I'll get you some pics next week - I am out of town shooting High Power for the weekend.

chr

 

[snakeraper11b]

This was the thread that got the ball rolling for me.
http://www.svtperformance.com/forums/showthread.php?709082-Rear-strut-brace-worth-it#post9857870

Looking forward to seeing iismet's solution as well.

 

[iismet]

YMMV

 

[03 DSG Snake]

YMMV

Very nice setup. I have a Hans rear STB that I have yet to have welded in yet. I wouldn't mind all the additional support that you rigged up as well as seam welding the towers. Now I just need to find a reliable spot to do it.

 

[iismet]

Very nice setup. I have a Hans rear STB that I have yet to have welded in yet. I wouldn't mind all the additional support that you rigged up as well as seam welding the towers. Now I just need to find a reliable spot to do it.

Thanks - its was some work but I'm glad we did it. I have a MM 4 point sitting in the shop to install. I am thinking of ditching the legs and going to the top of the towers. It maybe we put the legs in as designed but add an X to the top of the towers.

 

[snakeraper11b]

Not too rough of an idea for a home made solution. Where did you get the plates made that attach the shock mount to the floor?!?! Those things are bad ass

 

[iismet]

We fabricated them.

 

[03 DSG Snake]

What is the purpose of seam sealer? Is it to soak up vibrations/moisture/etc in the cracks between panels? Is this removed best using the dry ice method or what?

How could it be replaced after seam welding? I am looking at having just the towers seam welded along with the installation of Hans rear shock tower brace:

 

[iismet]

The panels are spot welded together. I was always under the impression the sealer was to assure any gaps were filled to keep water out of the trunk area. As I remember I used a wood chisel to scrape it out and then a rotary wire brush to clean. How does that brace attach? It looks like the gaps are large at the vertical walls. Does it weld just at the top?

cliff

 

[SVT_Troy]

YMMV

This is one of the most functional looking rear shock tower braces i think iv'e seen.
Is there anything special i need to know to mimic your setup other than welding the strut tower seams, welding in plates for the bars then welding in the bars? Did you mock up and weld everything with weight on the wheels?