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Have a look at the fun way in which the spindle (Vertical arm) has moved forward

relative to the upper link - about 3mm. Apart from killing my caster

adjustment it has barked the upper arm & squeezed the rear bush & ferked

it. This is on the LHS ie the unloaded side at the track. Haven't had

time to check the other side.

How can I stop this from happenning again?

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Edited by djr81
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i'm guessing it's the effect of running lots of caster. dont know how to stop it other than to run less. :teehee:

hmm i was going to use bushes in the upper arm to, but having seen that i may replace it with an adjustable, rose jointed arm. it may be harsher but at least i wont end up with a 'dynamic wheel alligment'.

LOL...i get about 18 months from a set, i always thought it was because i tend to let them run a little dry, but your look to be all nicely greased up?

My current set have only seen abotu 6 months of driving, with about 12 months of the car sitting around, but will be tryign the Noltec upper arms when these ones die (which they will)

but will be tryign the Noltec upper arms when these ones die (which they will)

yeah that's what i was thinking brisby. but wont they suffer the same fate? they are the ones that are in two halves right? and one half slides in and out of the other (for the camber adjustment), but they still have urethane bushes at each end.

hmmmmmmmm

when i got a few things done on my car and recent wheel alignment, I asked for 9 deg positive castor. They said they could only go 7 deg because they were worried about the control arm bushes. now i see what they were worried about!

..... anyway, i don't care, next alignment, i'm going 9 deg. it's worth replacing the bushes every 6 months!!

hmmmmmmmm

when i got a few things done on my car and recent wheel alignment, I asked for 9 deg positive castor. They said they could only go 7 deg because they were worried about the control arm bushes. now i see what they were worried about!

..... anyway, i don't care, next alignment, i'm going 9 deg. it's worth replacing the bushes every 6 months!!

Up to you, but I wrecked the bush during the course of one track day. At $300 per kit plus fitting I can think of better ways of spending my money. :)

Guess I am going to have to wind out some caster.... :thumbsup:

Interesting...i suppose check the basics like the bolts were torqued up enough...properly lubricated, the upper arm is actually round and not elongated...they were the correct part number???

I dunno, i know i have had problems with them as well, never one track day though, but yeh i get about 25-30,00kms from a set...which in my eyes is nto that flash :thumbsup:

From fitting these parts myself all i an say is they dont go back in as easily as they came out :)

However they will fit and do work a charm.

Reading they are only going to last 25k isnt that crash hot though :)

When i have tha car on the wheel aligning machine they are a pleasure to adjust ;)

Caster is maxed out around 7 with the whitlines bushes if it means anything to anyone. :thumbsup:

I have already sent a PM to Richard on this subject, to summarise............

Check the travel, the only time we have damaged a camber bush on the track was when the suspension travel wasn't sufficient. The bottoming out on the bump stop transmitted the load to the bushes. The next closest flexible medium.

The old faithful "cable tie on the shock shaft" test of travel is the easiest method to determin if that is an issue.

There is a limit as to how much caster you can run, the radius rod bushes in the Group Buy kit are pretty close to the limit when adjusted to their maximum positive caster position. From memory Richard is using adjustable caster rods with spherical bearings, this means 2 things;

1. It is possible to exceed the limit of distortion that the upper and lower control arm bushes will tolerate. In extreme cases, the lower control can actualy bind at the pivot point in the front subframe.

2. Any impact is passed on by the inflexible radius rod and transmitted to the attached suspension components. This being the upper and lower control arm bushes, once again being the next closest flexible medium.

Double wishbone suspension in not like MacPherson strut, where you can wind on as much caster as you want. Distortion of the upper control arm has to be considered. What I would do to check the level of distortion;

A. Remove the wheel and the shock/spring unit and disonnect the stabiliser bar links

B. Set the caster and camber to the desired settings

C. Jack the suspension up and down and watch the upper and lower control arm distortion.

D. Adjust (back off) the caster such that the distortion is at an acceptable level

>_< cheers :angry:

The suspension travel issue sounds spot on...my cars springs had some issues which meant a lower then usual ride height...at the track i was hammering the bump stop with a front ride height of 315mm...the dead control arm bushes coincide with this issue...which didnt get identified and fixed until the installation of the latest set...a bit slow identifying the spring problem.

So with the new Cusco castor arms and Noltec upper arms what would be the ballpark castor setting...as i have been told thats why im struggling in slow corners with the 4-5 caster i have with the Whiteline bushes

The suspension travel issue sounds spot on...my cars springs had some issues which meant a lower then usual ride height...at the track i was hammering the bump stop with a front ride height of 315mm...the dead control arm bushes coincide with this issue...which didnt get identified and fixed until the installation of the latest set...a bit slow identifying the spring problem.

So with the new Cusco castor arms and Noltec upper arms what would be the ballpark castor setting...as i have been told thats why im struggling in slow corners with the 4-5 caster i have with the Whiteline bushes

Let's start with the Noltec upper arms, Greg knows this, so I am not speaking out of school.

They slip, they rely on the friction of the bolts (small) to hold the two parts of the arm together.

Fairly quicky the bolts work loose from the twisting plus end loads and they start sliding.

There is another design around, similar to the Noltec upper arm, but with a longitudinal retaining bolt and 2 nuts that prevent the halves from sliding over each other.

215 mm front ride height is definitely an issue, as you have identified.

We don't have any problem with achieving 6 degrees caster and 3.5 degrees negative camber, using bushes in the radius rod and the upper control arms. Getting to 4 degrees negative camber and maintaining 6 degrees caster is tricky though. You can get more caster by spacing the upper arm inner mount rearwards at the chassis mount. The bushes protrude from the arms by 20 mm. So you trim 5 mm from the rear bush and use 5 mm of washers between the front bush and the mount. This moves the top mount of the upright rearwards 5 mm, giving more caster without loosing any camber.

Using these sorts of settings will increase the loadings and cause premature wear of the upper and lower control arm bushes. No one said motor racing was cheap.

>_< cheers :angry:

We don't have any problem with achieving 6 degrees caster and 3.5 degrees negative camber, using bushes in the radius rod and the upper control arms. Getting to 4 degrees negative camber and maintaining 6 degrees caster is tricky though. You can get more caster by spacing the upper arm inner mount rearwards at the chassis mount. The bushes protrude from the arms by 20 mm. So you trim 5 mm from the rear bush and use 5 mm of washers between the front bush and the mount. This moves the top mount of the upright rearwards 5 mm, giving more caster without loosing any camber.

Using these sorts of settings will increase the loadings and cause premature wear of the upper and lower control arm bushes. No one said motor racing was cheap.

>_< cheers :angry:

I have looked at the design and wondered about that...so it can/does happen?

Also whilst i may regret moving away from the offset bush approach which has served me so well, knowing that i have been able to get 3-3.5 neg camber and about 5 degrees of caster with the bushes...i cant ignore the fact that every car i have driven with rose joint caster arms (Nismo/Tein etc) have all turned a lot better then my car. I was hoping the Noltec solution to adjustable camber was going to be the solution, hoping that such arms had been R&D by plenty of club/circuit cars....

I hate this, i was thinking about actually making my own upper arms to the required length to get the camber i need...i know the Nismo arms work in a similar fashion

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