Im sure it's been done to death but I cant find an answer. Is it a good , bad or indifferent idea to increase the castor on a Z4 by fitting offset lollipops. This is for purely road use on otherwise stock suspension, the aim is to improve the directional stability. I have done the sticky steering tyres etc and things are much better at speed but it still doesnt really like road camber changes so suspecting the bushes now. Which way to go ?
Stock or M castor for an Si
- Thread starter legin
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I’ve not got offset bushes but I’ve got ST XTA coilovers which have castor adjustable top mounts. I am now running c7 degrees of castor vs stock of just over 5. It makes a positive difference to the steering in my opinion - principally it increases the weight off centre, but also quite noticeably reduces the kick back through the wheel from road imperfections. It makes the car noticeably easier to place on the road. It’s feels a bit less darty to small steering movements but is more stable at speed, and with the additional camber in sharper turns that comes with increased castor, it resists understeer well. Based on my experience, I’m an advocate.
The downside for me of offset bushes is that they push the wheel slightly forward in the wheel arch. Given I run M size tyres that would cause rubbing issues, and I suspect might also if you ran spacers on standard tyre sizes. But I’ve not tried it so will leave others to confirm or otherwise.
The downside for me of offset bushes is that they push the wheel slightly forward in the wheel arch. Given I run M size tyres that would cause rubbing issues, and I suspect might also if you ran spacers on standard tyre sizes. But I’ve not tried it so will leave others to confirm or otherwise.