Its where you unbolt the rear pivot on the back of the arm and rotate it 180 degrees and re-bolt it down. The rear pivot is offset so rotating it causes the rear of the arm to move outward, which means the hub is placed further forward increasing the angle of the strut for more castor. You can take it a step further by adding spacing plates between the rear pivot and the arm to increase castor some more.

A pretty much cost free way of adding more castor to your car. without the need for castor strut tops. Although it is a fairly small increase, every little bit helps. Because of this, my front wheel as moved forward around 7-8mm. Slight increase in wheel base helps with weight distribution too I suppose.

I did the castor mod and also added a 3mm spacer in. Going in for an alignment at wheels world this Tuesday.

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RS Liberty - Because WRX's are only good for parts...