Do eccentric bushes have fixed castor or need castor set up?

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Alburglar
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Sun Jul 05, 2009 4:19 pm

Hi folks
If I fit eccentric bushes front and rear, will I need to set the castor at a garage? or are they bolt on and go?.
Ali
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mt1104
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Sun Jul 05, 2009 4:29 pm

if you put them all in the right way you should be good to go.
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caneswell
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Mon Jul 06, 2009 6:46 pm

If you are talking about the offset front control arm bushes then there is nothing to adjust you just fit them.

Castor doesn't really exist at the rear. I take it you mean camber? If you are just fitting eccentric trailing arm bushes then you can't adjust them once they are fitted, they need to be pressed in the correct orientation to give the desired change. Might be an idea to get a garage to do this, if you can find a mechanic with a brain.
Black_Potato
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Mon Jul 06, 2009 8:47 pm

Your choices for setup are based on what is adustable, if not you fit what you have and then do what you can and on many cars that will just be the toe. To effect much else you need specifically adjustable components, on the front that would normally be via motorsport top mounts, on the rear you would need to use eccentric bushes as you suggest but setting them up would require some knowledge of the topic.
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geoffrey
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Tue Jul 07, 2009 9:05 pm

Set the eccentric bushes so that the arm is as far out as possible for maximum caster. In the past i've had the bushes rotate when on the car so every set i have fitted since i have drilled through the wishbone and bush and driven a small self tapping screw through the wishbone and just into the bush so that it can not rotate.

In case you are wondering what caster does, it gives you camber gain with lock. this is obviously an advantage when entering a corner. The downside of caster is heavier steering but the amount you will add with eccentric bushes is not enough to be felt through the steering.
Alburglar
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Tue Jul 07, 2009 11:41 pm

Ok, thanks guys. I think I will go for eccentric front bushes and concentric rear bushes unless anyone can see a problem with that?
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JimmyC
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Wed Jul 08, 2009 9:06 am

You can buy adjustable rear bushes, allows you to dial into your needs
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caneswell
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Wed Jul 08, 2009 2:02 pm

JimmyC wrote:You can buy adjustable rear bushes, allows you to dial into your needs
I thought they were fairly unsucessful though. Not offering much adjustment or moving on their own??
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