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suspension geometry / steering arms Luego
alfas - 26/7/13 at 04:21 PM

can you be so kind and check the following pictures for the angle of the steering arms and possible faults, incl. some ideas how to solve those faults? chassis is a live axle Luego from 2001.

view from front:
due to my knowledge the arms should be parallel to the ground, actuall they are inclined. lowering the steering rack would mean to modify the mounting points on the chassis. the lower wishbones arent perfectly parallel to the ground, too. i cant lower the spring seat on the coilover as the thread is near the end, also the coil already loose when the car has been jacked up. do i need new, softer coils?




view from top:
the steering arms are slightly angled, too.



[Edited on 26/7/13 by alfas]


Andybarbet - 26/7/13 at 04:33 PM

Are they cortina uprights ? They look different to my sierra hubs.

I have a later XT velocity but unfortunately dont have the hubs & wishbones on it yet, im sure someone will be along to help soon though.


stevegough - 26/7/13 at 05:00 PM

They are Cortina uprights, the angles look reasonably ok.

The point here is - why are you asking? Are you having problems eg bump-steer or lack of self-centering?

The angle the wishbones make with the ground is more down to the ride-height that has been set with the coilovers than any issues with suspension geometry.

I have just been trying to find a similar photo in my archive, I haven't got any, so I will go out and take a few. You / we can then compare them.

Give me a little while.


stevegough - 26/7/13 at 05:28 PM

Pics as promised!






unijacko67 - 26/7/13 at 05:31 PM

Could you lift the rack ? my point being you could get some different track rod ends and bolt them onto the top off the steering arm and also move your rack forward if poss. Not sure if it will help as only commenting on a picture so please find out more if my suggestion's are possible. Cheers


black fingernail - 26/7/13 at 06:45 PM

It looks like the steering rack is too high, I think the bottom wishbone should be parallel with the track rod to avoid bump steer, like on the above pictures. I know mine are.


rusty nuts - 26/7/13 at 07:35 PM

quote:
Originally posted by unijacko67
Could you lift the rack ? my point being you could get some different track rod ends and bolt them onto the top off the steering arm and also move your rack forward if poss. Not sure if it will help as only commenting on a picture so please find out more if my suggestion's are possible. Cheers


Cortina steering arms are design to have the track rod end fitted from below, that means the wider part of the tapered hole is at the bottom so fitting a different track rod end will not work without re boring the taper . It may be possible to use a rose joint with a tapered stud coming up through the steering arm to get the rack level . Has the OP checked the suspension with the driver in place


alfas - 26/7/13 at 08:28 PM

i asked cause it looks different to my ๓ther seven-type cars i owned. also steering is a bit "nervous"

pictures from steve looks similar, so nothing to worry in my case?

i dont know if those uprights are cortina or escort, but the donor car, according to the paperwork, was an 1978 escort.

indeed the steering arms are mounted from the bottom, the nut comes from the top. here another pic:



ah...what i forgto to tell: bumpsteer isnt really present...so not a problem.


[Edited on 26/7/13 by alfas]


unijacko67 - 26/7/13 at 08:35 PM

As above the steering arm and wishbone's should all be parallel to the ground and in a straight line when viewed from above. you can't go lower with the rack for your chassis, but you could find out the biggest bolt size that fits through the steering arm (smallest end of the taper) and get the same size rose joint then simply make a distance pies, tube with the corresponding nuts each end, one for the rose joint thread and one onto the rack. You may then be able to lift the rack so it lines perfectly.

Like this Description
Description


Try to make it adjustable so you can raise it or lower it for testing.

If as I've just seen you post no bump steer, forget all that and check tracking and set it to zero toe or check that its not more than 3mm toe out. Could be an easy fix, but could effect how your car turns in.

[Edited on 26/7/13 by unijacko67]


alfas - 26/7/13 at 08:38 PM

ok..that would be a solution...but what i want to know: where is the mistake here:

using cortina uprights?

wrongly welded chassis in terms of steeringrack fixing points?

coils to hard?

[Edited on 26/7/13 by alfas]


unijacko67 - 26/7/13 at 08:44 PM

If as I've just seen you post no bump steer, forget all that and check tracking and set it to zero toe or check that its not more than 3mm toe out. Could be an easy fix, but could effect how your car turns in.


britishtrident - 26/7/13 at 09:55 PM

First thing there is no way to tell just by looking at the angles of the wishbones and track rod, all cars are different apart from anything else the car is not loaded with the drivers weight.
There are a lot of old wives tales about the lower wishbone or track rod should be parallel to the ground.

If the car is twitchy the first thing to do before getting the car corner weighted and bump steer corrected is just a basic check on the the toe angles front and rear.

For road use under no circumstances do you want toe-out toe-out front or rear will make the car very twitchy.
On the front toe-out destroys straight line stability and makes the car over sensitive to steering input, bumps in the road, on the rear you get all of the above plus instability when applying power or braking.

The front toe should be set to parallel to 0.2 degrees toe-in, on the rear aim for a little more toe-in no hard and fast rules but around 0.25 degrees will work.


If you really want the car to handle like single seater you should get a proper setup done covering bump steer corner weights thrust line and damper settings.



[Edited on 26/7/13 by britishtrident]


alfas - 27/7/13 at 05:14 PM

the car is for road use only....so i will get the tracking, camber and castor set to the correct values first.

rear can only be checked, as its a live-axle.
by the way: on escort uprights the steering arm is also mounted from bottom.



[Edited on 27/7/13 by alfas]


britishtrident - 27/7/13 at 09:25 PM

rear Toe out on a live axle is quite common on the rear can fixed by running a couple of dummy weld down the opposite face of the axle tube from welds for the brackets.