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At the expense of being repetitive, this was meant to be nothing more than a exercise of how one design compares to another. I don't think for a moment the results tell anything more than that. In order to get absolute accurate results, I would need to model the exact structure as built, the real suspension with coil springs and shocks would need to be included, as Frank pointed out you can't really fix one side and load the other becuase in reality as you enter a turn one corner loads up while another releases. What I assumed for this exercise was a worst case scenario where one corner of the car would would remain fixed and roughly 25% of the cars weight would load up with a total spring rate adder plus a small percentage to create the load. I don't think we can read anything into the results other than all things being equal, what one design along with the Export Brace offers to our cars.
 

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Analysis Results Revision

So I changed the direction of loading on my previous model to be in line with the MC Bar. Again, these results are probably not 100% representative of real world scenarios. But they do show a good comparison of what does what. Again, curved bar helps, straight bar a little better, Z-Ray bar a little better than that.

https://dl.dropboxusercontent.com/u/79072616/Mustang/Monte Carlo Bar Comparisons A.pdf
 

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Discussion Starter #504 (Edited)
So I changed the direction of loading on my previous model to be in line with the MC Bar. Again, these results are probably not 100% representative of real world scenarios. But they do show a good comparison of what does what. Again, curved bar helps, straight bar a little better, Z-Ray bar a little better than that.

https://dl.dropboxusercontent.com/u/79072616/Mustang/Monte Carlo Bar Comparisons A.pdf
Patrick, if you don't mind drawing a conclusion, or making an assumption based on what you have done so far, I have a question for you: since my MC bar is farther forward than the "stock" straight MC bar, I am surprised that it comes off as being slightly more rigid than the regular straight bar. The best I was hoping for was a design that would equal the straight bar.

The stock straight bar, being closer to the shock towers where all the "action" is coming from, is admittedly in a better location than mine. I was thinking that my auxiliary strut tubes would just compensate for the more forward location of the main tube. Of course it sits farther forward only out of necessity in order to clear carbs, or air cleaners, distributors, etc.

The only thing I can think of is that having multiple tubes mounted against the shock towers & fender aprons adds slightly more effectiveness than I was counting on.

Any thoughts on that ?

And again, thanks for your efforts for all concerned.

Z.
 

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Z, I think the only conclusion I could draw from this is the triangulation affect your bar offers is providing additional stiffness preventing the top of the shock tower from folding in towards the center of the engine bay. If you look closely at the small orange area on the top of the right shock tower and compare the deflections in those areas you will see a noticeable difference. In the straight bar design it deflects between .065-.075 inches. In your design the range is between .047-.053 inches. Comparatively speaking, the curved bar is around .090 inches. Under hard cornering these values might not be far from unrealistic.
 

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I think a lot of folks are missing the most important point here, when discussing the merits of the straight MC vs Curved MC vs the Improved Straight MC...

Will the new bar come in red?
 

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Looks like a nice FE model Patrickstapler! The tricky part with modeling these bars is the boundary conditions at the ends. The stock bars with the flimsy metal brackets are somewhere between fixed and pinned (moment springs would mimic this although the K factor is hard to predict without testing). I assume your model uses a fully fixed. ZRAYs are closer to a fixed condition (on two of the three axis) and would likely provide a bit more separation of results. Good job, that definitely took some time.
 

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Yeah I assumed fully fixed at one end. I think I pointed out in one post that wouldn't be realistic. But in reality the loading condition isn't completely accurate either. To get closer to reality I would need to provide a release in the vertical axis on the passenger. I would also need to model in the suspension geometry along with spring rates. But then again, I would also need to add the rest of the structure of the car. After running several iterations of this model I realized how important one part plays on the other in the structure of our cars. It turned out to be a very educational exercise...for me at least.
 

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Patric wouldn't the spring and upper control arms also change the forces on the shock towers,possibly dynamically?

seems the higher rate spring would try to roll the top of the shock tower more than a lighter spring rate.

As I said above the front feels different now with the bar installed.
 

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The springs would definitely have an affect. To what degree I'm not sure. My first instinct would be that they would decrease the overall shock loading on the structure. But that's why I previously mentioned to be more accurate they would need to be included.
 
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