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Libra Steering Geometry
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Author:  Spider [ Mon Jul 20, 2020 4:53 am ]
Post subject:  Re: Libra Steering Geometry

I have manufactured a pair of the revised steering arms and very happy with the result. I fitted them to the car in their "flat" state (no bend) and will probably leave them that way. That will produce a small increase in bump steer but I am thinking of reducing the castor slightly to correct that. I am thinking of removing one shim from the front upper wishbone mount - this will reduce caster, create some negative camber and move the tie rod end forward, making the tie rod more parallel to the rack and increasing Ackerman. Does anybody have experience of changing these shims? Are the nuts attached to a spreader plate behind the fibreglass or do you need to access the nuts? (looks impossible)

There is plenty of clearance around the tyre at full lock and the turning circle is now much tighter.

Steering response is much quicker as you would expect - I am happy with it now even though my car has the slower steering rack.

Tyre scrub at parking speeds was not noticeable but I still need to test on some smooth concrete.

Tie rod adjustment required is about 15mm longer - you may need longer extenders. (This will be less than 15mm if I adjust the alignment as mentioned above).

Author:  sanzomat [ Mon Jul 20, 2020 8:35 am ]
Post subject:  Re: Libra Steering Geometry

Spider wrote:
Are the nuts attached to a spreader plate behind the fibreglass or do you need to access the nuts? (looks impossible)
.

Hi Spider, Unfortunately the nuts aren't captive, just standard nylocs. Access is a pain (quite literally). There are access holes in the bulkhead/kick plate box section. Have to remove the carpet and there should be some bits of hardboard or similar glued over the holes so remove those too. You can then get an arm holding your 10mm spanner through the access hatch by lying in the footwell. Particularly hard on the driver side as you have the pedals and steering column in the way too. Your are likely to get a bit of glass rash where your wrist/forearm rubs on the opening edges too! Have some spare M6 nylocs as if you drop one you may not be able to reach to retrieve it and it'll annoy you forever rattling around in the box section!

Author:  Spider [ Mon Jul 20, 2020 11:13 pm ]
Post subject:  Re: Libra Steering Geometry

Thanks sanzomat. Amazing how a small omission at the design stage can cause so much grief for the end user.

Author:  Stevepi [ Mon Apr 26, 2021 1:28 pm ]
Post subject:  Re: Libra Steering Geometry

Had lots of experience of the nylocs from hell on my rebuild.
I found it a lot easier to take the pedal box and heater blower out.
That way its a one man job as you can get to both sides from above very easily. :D

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