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Eccentric front UCA bushings positioned downward for more camber gain?

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Old Feb 22, 2017 | 11:35 AM
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Eccentric front UCA bushings positioned downward for more camber gain?

Based on tire wear and pryro data, I am installing whiteline front upper control arm (UCA) bushings in an effort to gain more camber. However, I started thinking about how to position them.


Full inboard would give the greatest static camber gain without a change in camber gain rate.


BUT, if I install the eccentric hole downward, that would impact static camber very little, but introduce a more aggressive gain rate as the car rolls.


Has anyone tried installing with the holes downward so that braking camber isn't affected as much, but the car gets a nice camber gain in the corners?
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Old Feb 22, 2017 | 07:57 PM
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That's an interesting idea. You'd have to measure the camber curves before and after to make a determination if the change was significant, or do some controlled testing at a track.

One problem is that under dive, you'll still get an increase in camber, unless you're stiffly sprung or have a lot of damping. You may also increase brake dive by changing the anti-dive geometry in the front suspension.
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Old Mar 2, 2017 | 12:52 PM
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Originally Posted by hufflepuff
Based on tire wear and pryro data, I am installing whiteline front upper control arm (UCA) bushings in an effort to gain more camber. However, I started thinking about how to position them.


Full inboard would give the greatest static camber gain without a change in camber gain rate.


BUT, if I install the eccentric hole downward, that would impact static camber very little, but introduce a more aggressive gain rate as the car rolls.


Has anyone tried installing with the holes downward so that braking camber isn't affected as much, but the car gets a nice camber gain in the corners?
I was just looking at these.

are you going to be at these TD events?
4/22 SPJ

5/6 DOM
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Old Mar 3, 2017 | 06:07 AM
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Not those two. But i'm planning on the TD 17 June SPS and June 23 DR events. I'll be doing mostly NASA, with some SCCA/Chin/HOD/Trackdaze events this year.
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Old Apr 14, 2017 | 02:55 PM
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did you install these offset camber bushings yet? how did you orient them in the end?
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Old Apr 14, 2017 | 04:04 PM
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For now I have the holes fully outboard for max camber. I only have my lower control arm eccentric bolts at the half way point and I'm at -2.5 with a 13.5" ride height.
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Old Apr 14, 2017 | 08:30 PM
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how much negative camber did you gain from the bushings? and have they moved on you at all since hitting the track?
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Old Apr 14, 2017 | 08:46 PM
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are they these?

Whiteline KCA421

they barely look offset (if they are)... or am I looking at the wrong ones?
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Old Apr 14, 2017 | 09:05 PM
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Yes those are correct. They claim to gain you 0.5 degrees either way.

With the upper offset bushings​ maxed and the LCA eccentrics maxed, my car looked helladumb and broken... Probably about 4 degrees negative at 13.5" ride height.
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Old Apr 15, 2017 | 01:29 AM
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Originally Posted by hufflepuff
For now I have the holes fully outboard for max camber. I only have my lower control arm eccentric bolts at the half way point and I'm at -2.5 with a 13.5" ride height.

Fully outbound? Don't you want the uppers in and the lowers out?....
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Old Apr 15, 2017 | 05:53 AM
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Originally Posted by dannobre
Fully outbound? Don't you want the uppers in and the lowers out?....
when the UCA holes are rotated fully outboard, that moves the UCA fully inboard, increasing camber
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Old Apr 15, 2017 | 08:41 AM
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Originally Posted by hufflepuff
when the UCA holes are rotated fully outboard, that moves the UCA fully inboard, increasing camber
LOL. Wasnt awake when I read that 😐
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