Just wanted to say 'hi' to fellow Libra owners here!

Hello and welcome

Being a fairly recent convert to the Libra, and not having built it myself, I have a lot of questions, and was hoping this migth be the place to help answer them...

The first thing I was wondering about was if anyone had changed their steering rack for something with fewer turns lock to lock? Mine's obviously a standard LHD metro one, and I was wondering how easy it might be to source something that turns a bit quicker. I had heard it was pretty much impossible, but anyone know different?

I'm by no means an expert on this - and I don't know if the metro rack changed over the years, but the old Metro challenge cars might have had a quick rack????

But were they left hand drive though?

I agree that fewer turns on the steering would be better (the standard LHD metro rack is used to keep costs down). There is a Libra currently advertised on Pistonheads that is said to have a quick rack.
http://www.pistonheads.co.uk/sales/553530.htm
http://lyndonevans.blogspot.com/

Must admit I had seen that advert, which is partly what prompted the question. So it definitely looks possible, but it's sourcing a quick rack for a left hand drive metro... I don't really know where to start looking. I might have to email the chap selling his Libra!

In fact, I just have. I'll let you know what he says in case you are interested.

Well, I got a reply. Apparently the rack is off an MGF rather than a Metro, which seems a bit odd as the manual clearly states the standard one is off a Metro but hey, maybe they are the same size. He's going to look out the contact details of the chap he bought it off... investigations will continue!

MGTF I think, you will need to contact GTM for different steering arms ?

Found on the GTMOC Yahoo Group: -

Re: Libra Quick steering

It is possible to use a MG TF rack (2.8 turns lock to lock). GTM can supply
the shorter steering arms.

Guido
http://www.gtmv6.com


--- In gtmoc@yahoogroups.com, "gordon_tyreman" <geologistrig319@a...> wrote:
> I haven't seen any info about steering mods on the Libra so here are
> some thoughts. When I first drove my Libra I realised that the
> steering was very light and also very low geared for a sports car at
> 3.7 turns lock to lock. I decided that this did not give sufficient
> feel and also precluded the possibility of getting sufficient
> opposite lock on if the back end ever decided to drift. The
> modification I have made has I believe significantly addressed and
> improved these two conditions.
> The steering rack on both the metro and Metro gti are the same but
> stops are added to the gti to prevent fouling by the wider wheels so
> either rack can be modified to the same effect.
> The GTM steering arms are effectively 140mm long from notional king
> pin centre to centre of the track rod end. This can be shortened by
> whatever you feel will give you the characteristics you desire. I
> modified mine by shortening to 100mm ie remove 40mm from the steering
> arm and machine a new morse tapered hole (cost 25 quid at the local
> engineering shop) This gives you a comparable lock to lock of 2.6
> turns, though in effect this is more because the new lock with
> shortened arms is considerably tighter. The new lock gives no
> problems of fouling on the body work, in fact the first place the
> wheel touches is the wishbone. A few words of warning here, the MOT
> requires the wheels do not foul on the body or suspension so jubillee
> clips can be added to limit the extremities of lock. Also the
> steering arms supplied by GTM are angled inwards at the front in a
> plan view and also ramp up and then level out in the side view. These
> angles are intimately related to the steering geometry and cannot be
> ignored.
> For this reason the maximum reasonable reduction would be to the
> point at which the arm starts to ramp up ie 40mm from the original
> track rod end location. Also because the act of relocating the track
> rod end rearwards also moves that point outwards the new mounting
> point must be drilled 3.5mm inboard of centre to restore the
> geometry. If this is not done accurately then hideous bump steer will
> result. In fact I did not allow for this and had to heat and bend the
> steering arms to restore perfect geometry. The result is that
> steering is now a bit heavier at parking speeds but not oppressively
> so and feel and response are much improved. I know one or two other
> people have made similar mods; subsequently Bryn reduced his by 20mm
> and that was a good compromise I believe. Of course the new offset
> for the tapered hole would in that case be about 1.8mm to eliminate
> introduced bump steer.Because reducing the steering arm length
> effecively reduces the Akkerman steering geometry you should
> compensate by reducing toe-in. In fact I run 2mm toe out and the
> steering feels great and tram-lining is reduced, with no tyre wear
> problems. If you feel the steering needs more feel and responsiveness
> don't hesitate to do this modification I am extremely happy with the
> results I have achieved . Gordon

Shorter steering arms made the steering to quick and was never a factory option. The factory quick rack was the LHD rack from a MG TF160 with standard steering arms. Some people have fitted the steering arms so they are toeing out instead of in (swap side to side), this increases the ackerman geometry and self centring, which made it feel better. Can’t remember if the steering arms needed shimming to correct bump steer when you swapped them around? You need a bump steer gauge to check it.

If I remember correctly the short steering arms gave it negative ackerman like a F1 car.

i dont understand why it has to be an upside down rack?

When we say shortening the steering arms gives quicker turning is this the steering rack arms or the arms that are bolted to the hubs.. ?

The steering arms bolt to the hub and connect to the trackrod end.

Thats what I meant (: