At my last a/x I noticed the wing was not sitting level and was leaning on one side. Upon closer inspection the left mounting bar was cracked at the weld to the tranny support. The arrow in the photo below points to the area of the weld. I'd show you a close-up pics but the weld was so shitty I'm embarrassed to show it. I never really liked how I fab'd it in the first place so this gave me a chance to do it right. The new mount will allow me to be able to attach a lower rear diffuser in the future.

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How much weight will a better weld add?

I cut the bars and the support off completely and started fresh. I had a piece of 1/8" sheetmetal formed and I welded it between the tranny supports.


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Gee that smart ass remark didn't take long.

Sorry, it happens.

Next I had a piece of 1/8" aluminum made to fit over the sub-frame and bolted it on.


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Then bolted the wing supports to it.


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That's a nice looking setup. Doubt you'll have issues with it. Beautiful work by the way.

I also added cable supports to the wing at the top of the supports and welded tabs to the roll bar under the targa bar. I used small aluminum turnbuckles to tighten the cables and installed them diagonally in an X from the wing to the roll bar tabs.

I also made larger wing end plates out of 1/16" aluminum sheets. The old end plates I made myself out of carbon fiber and fiberglass and were too heavy.

OK, now everyone can chime in and tell me how I should have done it different.

I also added the gussets to the inside and welded a plate between the bars on the outside so it is much much stronger. It strengthens the entire rear end. The ass end of it was always too weak and I'm sure it had some flex problems before.

Paul, broken weld at the mounting point = your downforce is working well.
Great looking rear trunk area, we have also joined the Trunkless Brigade
Must be a fun racer !
Marty

I think it broke for several reasons.

- The weld was crap.
- I leave the wing on when I haul it on my open trailer.
- It would vibrate/twist/shake around too much which placed added stress on the welds.

Yah yah, but you did not answer Woody,s question.

how much weight did you just add?

We need a vendor to produce Aluminum rear control arms!

Believe it or not I don't have a set of scales to weigh the car after I make a change.