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Cornering Optimizing your suspension system.

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  #16  
Old 12-10-2008, 01:33 AM
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that's what I'm talking about....the spacers. They still require you to switch up the tie rod.
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  #17  
Old 12-10-2008, 01:49 AM
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really... crap, I want to put the control arm back in teh possition it was in before i dropped the car.
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Old 12-10-2008, 02:40 AM
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The spacers would help that, but your tie rods would still be left at the position they were in after lowering. From what I've read, the fact that the control arms are back down to "normal" while the tie rods aren't will cause you to notice additional bump steer.
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Old 12-10-2008, 03:02 AM
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you shoudl go on aim :-D
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Old 12-10-2008, 05:40 AM
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Originally Posted by Rally View Post
I know ryephile raised up his streering rack while the VW guys make the changes at the other end of the tie rod with spacers or different mounting points.
Yeah, shimming up the steering rack is how most people go about it. Not sure if you can do enough on our cars to make a difference though, it's tight in there.

Ivan, true, but if you have droop at rest you're going to have some jacked-up roll center I would imagine. But, it's been a long day, I'll have to do some reading and come up with a more technical reason why they're a bad idea.
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Old 12-10-2008, 06:49 AM
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Adam what you said about it being useless on Mcpherson type suspension has to be explained to me, because in actuality Mcpherson type is completely affected by the geometry of the suspension. Bump steer is a common problem with the macpherson type suspension (which is what is mainly fixed with RCA). To put it in the simplest terms possible, If one were to run over a bump on the road with a vehicle with a Macpherson type and one were to do the same in a double wishbone the one with the macpherson would feel a harsher jolt. The reason being a double wishbone suspension has 2 A-arms in the assembly and the shock attaches before the hub, which means that it uses leverage from the lower arm to reduce the amount of shock to the vehicle as a whole, making it have less bumpsteer. Now the Macpherson strut has the shock attached straight onto the hub, so whatever the tires run over the vehicle is affected directly by it. So when a car with macpherson struts is lowered the arms sag in turn makes the track of the car slightly smaller, having less leverage than it already did, causing an increased amount of bumpsteer.

In other words in a Macpherson type suspension is essential to have roll center adjusters.

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  #22  
Old 12-10-2008, 07:02 AM
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The tierod ends on the other hand decreases the angle made by lowering the car and so gives you the lost steering response as well as returns the steering angle and adjustments that is possible at stock height. usually doesnt have anything to do with bumpsteer depending on vehicle.
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  #23  
Old 12-10-2008, 04:36 PM
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But again, if you install RCA's without altering the tie rods, the tie rods and control arms will no longer be parallel as required, which will in turn increase bumpsteer.
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Old 12-10-2008, 05:28 PM
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But again, if you install RCA's without altering the tie rods, the tie rods and control arms will no longer be parallel as required, which will in turn increase bumpsteer.
Exactly. With a McPhearson strut system you can [very] basically think about the tie-rod as the upper A-Arm in a double wishbone setup. You wouldn't want to alter one and not the other.

Edit: I definitely agree with Ivan, but I would think that the positive effect of dynamic negative camber would be more than offset by increased dynamic toe out (bump steer.)
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Old 08-31-2009, 01:35 AM
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Nothing super new....just new pic I found

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