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I finally calculated the forces applied to a strut tower in a 1G turn

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Old 11-19-2003, 01:21 PM
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Ken From KLA Industries
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Default I finally calculated the forces applied to a strut tower in a 1G turn

Well, I finally calculated the lateral force on the top of the strut tower during a 1G turn. The following web site gives great info on the suspension calculations and set up a spreadsheet to do the calculations.

I measured the ball joint to the ground (5.2”) and the ball joint to the top of the strut (23.5”) on my wife’s 951 and plugged these and the weight (2899) into the sheet.

In a 1G turn the outside strut tower is subjected to 641.48 pounds of lateral force. Now, we can measure the deflection in the tower by attaching a small bracket to the top of the strut tower and applying 641.48 pounds of force pulling outward and seeing how far the tower flexes. Before we get into the discussion about both towers flexing please read the discussion at this web site.

http://www.e30m3performance.com/myt..._bar_theory.htm

Ken
Old 11-19-2003, 01:23 PM
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Perry 951
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Nah-baba-nah on the link.
Old 11-19-2003, 01:26 PM
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SoCal Driver
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That's not correct. You need to use the center line of the spindle too. You also assume that there is no tire slipage.
Old 11-19-2003, 01:36 PM
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Epic2112
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Nah-baba-nah?

here's the correct link:

link
Old 11-19-2003, 02:01 PM
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Perry 951
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Originally posted by Epic2112
Nah-baba-nah?
It's a Cincinnati thing....
Old 11-19-2003, 02:19 PM
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Jon Moeller
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SoCal,
I'll agree with you on the need to integrate the center line of the spindle into the calculation, but the tire slippage is irrelevant. The cornering force is defined as 1g, thus the tires are generating a force equal and opposite to the weight of the car. Or, am I missing something?
-J
Old 11-19-2003, 02:24 PM
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Static calc verses dynamic. Now we just need to do a FEA on the whole front of the car to determine deflection at the top of the strut.

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Old 11-19-2003, 02:32 PM
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Fishey
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Originally posted by Perry 951
It's a Cincinnati thing....
Me and my roomates agreee... Its a Cincinnati thing.
Old 11-19-2003, 02:33 PM
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Jon Moeller
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Hence, the reason you are the 'Guru'.

Thanks, I enjoy the backyard engineering discussions. Especially when everyone else isn't a backyard engineer.
-J
Old 11-19-2003, 02:50 PM
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The 'Guru' is Rennlist indexing because of the number of posts.

In over 40 years of working on cars and sometimes making a living at real engineering I would not consider such a pretentious title. There is always much to learn.



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