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Eliminating Bump Steer on an FC.

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Old May 9, 2005 | 12:17 PM
  #1  
eyeoutthere's Avatar
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From: Owego NY
Question Eliminating Bump Steer on an FC.

I have a bump steer issue on my FC.

The car:
Lowered about 1.5”
1° extra of caster and 1.5° extra camber up front, otherwise factory alignment specs except.
Manual steering (power rack for a quicker ratio but no pump)
245/45/R17 R-compounds on all 4 corners.

We have been autocrossing on a bumpy lot and the bump steer is killing me.

Does anyone make rod ends to fix this? Spacing the steering rack is not an option because there is a motor in the way.

Thanks for any info!
-Jason
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Old May 9, 2005 | 04:51 PM
  #2  
diyman25's Avatar
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From: sca
you sure is bump steer? did you measure it ? or your shocks is button out ?
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Old May 10, 2005 | 04:29 AM
  #3  
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From: n
Jack the car back up.
Why you got it so low???


-Ted
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Old May 10, 2005 | 07:11 AM
  #4  
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From: London, Ontario
I can custom machine the parts you need. If you like, PM me.

-billy
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Old May 11, 2005 | 01:02 PM
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From: nunya
I noticed when I put camber plates on my bump steer disappeared, but also they lifted the car a good 1/2".... saggin stock rubber.
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Old May 11, 2005 | 01:20 PM
  #6  
Travis R's Avatar
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From: Austin, Tx.
If it really is bumpsteer it will need to be fixed at it's connection to the upright. You should get the car on a good alignment machine and measure the bumpsteer.
What is the offset of your wheels. You might also be feeling kickback through the wheel which is more a result of caster and scrub radius.
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Old May 11, 2005 | 03:04 PM
  #7  
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From: nashville
change ur balljoints
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Old May 13, 2005 | 10:08 AM
  #8  
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From: Edmonton, AB, Canada
Diyman 25, bump steer is when the steering changes with suspension travel due to a mis-alignment between the suspension arm geometry and the steering arm geometry. The best way to avoid the problem on a strut based car is to position the steering link directly in line with the lower suspension arm so the pivot points on both parts are the same. Most times this is not possible so you have to do the best you can. If the arms are parallel (steering and lower suspension arm) the effect is drastically lessened.

-Trent
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