 How flexible do you think a stock, trailing arm is |
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| ChrisFoley |
 Dec 16 2005, 06:19 PM
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#1
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I am Tangerine Racing  Group: Members Posts: 8,016 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None 
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Specifically I am looking for rotational stiffness (ie. twist) of the trailing arm due to the tire contact patch resisting sideways sliding of the car. I'm only interested in forces greater than 1G during cornering.
I already know what happens but go ahead and take a guess. (IMG:style_emoticons/default/biggrin.gif) I'll post pictures of my test fixture shortly. |
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| ChrisFoley |
Dec 16 2005, 09:36 PM
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I am Tangerine Racing Group: Members Posts: 8,016 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None
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QUOTE Unless you intend on making the stock trailing arm your "standard", you'll otherwise need to qualify your fixture. The area I never liked, was the pivot shaft and how it ties into the chassis mounts. Think about the camber and toe adjustment. You must deflect the inner ear in order to move it around. I've seen where some try to re-inforce the inner ear, only to have it crack. My research is primarily aimed at Production race cars that receive custom modifications by me. With that in mind I intend to make a fixture which will allow me to measure stock trailing arms for damage, and will allow me to make minor alterations to the relationship between the pivot axis and the axle axis, ie. static camber angle. When I raise the pickup points I use a 3/16" plate for the inner ear that is much more resistant to cracking than the stock sheet metal, yet allows for changes to the pivot shaft angle. The plate can be bent minutely if desired by striking it with a BFH. The range of adjustment necessary is very narrow so the stock system continues to be suitable for my application. My goal is always sophistication in planning and simplicity in operation and appearance. (IMG:style_emoticons/default/idea.gif) |
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Posts in this topic
Racer Chris How flexible do you think a stock, trailing arm is Dec 16 2005, 06:19 PM
TimT Chris the trailing arm appears to be a pretty sto... Dec 16 2005, 06:25 PM J P Stein WAG:
1 deg @500 lbs.
I'm assuming you're ... Dec 16 2005, 06:26 PM airsix What exactly do you mean by "1G". I'm sure you... Dec 16 2005, 07:09 PM ppickerell Chris,
Do you intend to test before and after boxi... Dec 16 2005, 07:41 PM Dave_Darling I'm guessing that most of the flex happens in ... Dec 16 2005, 07:54 PM spare time toys My guess is it has flex designed into it at an amo... Dec 16 2005, 08:08 PM Racer Chris So far JP is the only one really on the right trac... Dec 16 2005, 08:24 PM Racer Chris Then I attached a 5ft piece of structural tubing t... Dec 16 2005, 08:26 PM Racer Chris by putting a 200lb man's weight at the end of ... Dec 16 2005, 08:32 PM Racer Chris I had a friend sit on the end of the tube and saw ... Dec 16 2005, 08:34 PM Racer Chris I have several more tests planned already.
1) meas... Dec 16 2005, 08:40 PM TimT Put the level on the trailing arm, not the lever
... Dec 16 2005, 08:41 PM TimT and yes I see the angle you have welded on the bo... Dec 16 2005, 08:42 PM SpecialK ....go on.... http://www.914wor... Dec 16 2005, 08:43 PM andys Chris,
This is exactly the kind of testing requir... Dec 16 2005, 08:57 PM goose2 If you mount the level in various locations on the... Dec 16 2005, 09:06 PM TimT 
