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[terry paget]

I thank Nick W for advice  in this matter. I have now devised a technique whereby I can reset camber and toe in precisely and rapidly. This forum may not approve as some senior members dislike my supporting the front of the car under the wishbones. Recalling my schoolboy mathematics - the cosine rule - I calculate that 10cms extension or compression of the Mcpherson strut spring will increase camber by about 3 degrees. Therefore the setting of -1 degree 40 minutes when normally loaded, wishbone horizontal, is a compromise allowing for this. You see from pics I have set both front wheels at minus1.6 degrees. The tool I have used is the Budget Digital Angle Gauge with backlight, cost £20.50, works a treat. Pics also show how I support the car, and how I set the toe in by adjusting front wheels parallel to rear with steering wheel centred. I invite comments.

[url]https://www.dropbox.com/s/4efchsl265jjkff/camberNS.jpg?dl=0]https://www.dropbox.com/s/mb3wdyeukh6mspz/wbonesupport.jpg?dl=0[url]
[url]https://www.dropbox.com/s/4efchsl265jjkff/camberNS.jpg?dl=0
https://www.dropbox.com/s/7ct2y7r4578kovc/camberOS.jpg?dl=0
https://www.dropbox.com/s/nd9y02njilkua2w/tracking.jpg?dl=0

[terry paget]

Apologies, made pic error. Here is the nearside camber setting.
[urlhttps://www.dropbox.com/s/davvhxz9yyucwvz/NScamber.50%25.jpg?dl=0][/url]

[terry paget]

https://www.dropbox.com/s/davvhxz9yyucwvz/NScamber.50%25.jpg?dl=0

[Nick W]

How does the camber setting read when the car is on its wheels? I found it's just about possible to adjust it without removing the wheel or even jacking up the car. This was working in the street. Does need another person to help.

You need to check it again when you've adjusted the toe setting too.

I hope you are zeroing the gauge on the ground between the wheels. That needs to be done on a reasonably long straight edge, like a spirit-level.

Are you measuring anything at the rear suspension, or just hoping it's good enough? Adjusting the front on its own is fine on a simpler suspension system but can lead you astray on a sophisticated one.

[terry paget]

Thanks for the feedback Nick. For years I have been setting toe in with the front of the car supported under the wishbones, which works very well, always bang on first time. I believe I have now found a way of checking camber at the same time. Henceforth I shall do the camber first (wheels off), then the toe in with wheels on.

I found it quite difficult to adjust the camber. It is a 14 year old car and I presume it has not been adjusted before. Original settings were -0.5 left, -0.2 right. Bearing in mind the wide variation inherent in a McPherson strut/wishbone system I don't think it matters that much, but now I can set it I can see how tyre wear varies with camber setting.

The garage floor is horizontal, and I zeroed the gauge on a convenient steel vertical surface, part of the door frame, as checked with a spirit level.

I assume the rear is OK.

[chrisgixer]

https://www.dropbox.com/s/davvhxz9yyucwvz/NScamber.50%25.jpg?dl=0

I don't want to sound negative towards valiant attempts, but inevitably there are some major issues anyone reading should be aware of evident in this pic.

As Terry knows placing the entire wait if the car on the wishbone gives;

1 a good chance of bending the wishbone.
2 Risks damaging the rearward bush as the jacking point raises the wishbone up towards the subframe as you can see, this stretches the rubber up from the outer edge of the wishbone while the centre stays fixed.
3 the jacking point is inboard of the actual load bearing point of the wheel, so due to massive leverage of the normal load point being refused means the car is being set up to the incorrect ride height. This means when the wheel is refitted and the car lowered to the ground, the camber will be excessive.
4 as the gauge used is a level device, a couple of axle stands on blocks of wood doesn't mean the car is level relative to the gauge.

I'd strongly suggest taking a measurement from wheel rim to shock body as a guide, after the car has been set up correctly. Then use that measurement for future use. Your then working from known start point.

Having said that, the fact you have a pit means adjusting the camber with the wheels loaded / car on the floor "should" be fairly easy. A bit of tension on the shock bolts to avoid slop, but still allowing you to thump the wheel over at the top to achieve the correct desired camber should work as said.


Never jack on the dif. Never Jack on the wishbone. Dito stands.

[chrisgixer]

In all honesty these methods are not recomended as a final position. However highly recomended after suspension rebuild to try and get somewhere near the correct position until full set up is achieved professionally.

New suspension can take a few weeks to settle to its new ride height. So set up can be off if done too early anyway.

[chrisgixer]

That's also ignoring the fact that the desired camber setting is actually -1.10

[terry paget]

Thanks for your observations Chris. I am striving all the while to find a way of setting up the car. My experience of garages and tyre shops is abysmal. For decades I have had cars 'set up', and all they do is adjust the toe-in, usually on one track rod, leaving the steering wheel  not central on straight ahead running. Members still report suffering this. My method on tracking certainly does better than that.
I was always aware of risk of bending wishbones, but never have yet so think that can be disregarded. they are more at risk of bending when I fit them and I use a long lever in the hole to pull them down to insert the ball joint pin.
I appreciate I should support the wishbone directly beneath the hub to apply the correct leverage to the wishbone; it's difficult to do. Perhaps Sassenach was right when he said I should dispense with the wood block.
I depend upon the garage floor being level, and the axle stands and wood blocks being matched in height, both reasonable assumptions, another reason for dispensing with the wood blocks.
The pit was no help in setting camber, and little help setting tracking. I'm always afraid of falling into it, so in this job it's a mixed blessing.
 I don't believe camber affects the handling at all, but does affect tyre wear. I hope to find a setting that helps. Common sense suggests the wheel should be vertical in normal load straight running, yet Haynes states 1.6 degrees negative camber. I imagine this is to allow for the fact that this will go positive on suspension movement. At lest now I am able to experiment with different settings. In the past I have had Omegas where one front tyre wore evenly and the other wore badly on the inside edge.
It is easy for wheel alignment shops to measure all geometry parameters, more difficult to adjust them. Garages send customers' cars out to 4 wheel alignment specialists and they come back with impressive printouts of figures customers do not understand and mean nothing; waste of money.
Thanks for the feedback, it's much appreciated. This forum has a wealth of experience that makes running these old cars a pleasure.

[chrisgixer]

Haynes isn't called the book of lies on here for nothing Terry.

Camber is used to counteract cornering wear. If set to 0 camber, by the time the tyre is worn to zero tread the outside edges will wear more due to cornering. So a good set up guy (not the retards in tyre bays that state " needs tracking mate" to every wear issue) will see that wear and adjust the camber accordingly. A more exuberant driver will need MORE camber to counter the wear caused by faster cornering.

This is why standard suspension is set to -1.10 and sport suspension set to -1.15, as sport suspension presumes more exuberant cornering.

At NO point was 1.6 EVER considered anything other than disasterous.


Further, consider the accuracy needed to measure 0,05 minutes (not degrees) of camber, and consider the methods explained here. Such as;

The assumption the garage floor is level
The thickness of the wooden blocks
The height of the stands
The angle of the wishbone and the contact point along that angle
The failure to consider ride height at any point
The accuracy of that gauge, known to be dubious alone even without the other variables above
The fact the target set up figure us incorrect and unaware of minutes or degrees.

....and I'm sorry to say Tell, that this is fishing in the wind, especially if your looking for a final position. You'd be better with Dtm's method of adjusting the nub to max camber then "knock it back a bit"



But why are you not IN the pit, loosening the camber bolts wheels on car on the floor and adjusting camber that way, via the gauge? You'd be FAR better that way as it removes all the variables except the gauge itself. That's how the set up boys do it, albeit with a floating pad under the wheel, so you'll need to roll the car back and forth between each adjustment to take out the pinch on the wheels track.

[Shackeng]

Following this with interest as I expect to be changing shocks on the TD Estate in the near future. Regarding setting the camber with the correct ride height, I was told by a geo shop that setup should have simulated pax weight loaded into both front seats to achieve this.

[chrisgixer]

Following this with interest as I expect to be changing shocks on the TD Estate in the near future. Regarding setting the camber with the correct ride height, I was told by a geo shop that setup should have simulated pax weight loaded into both front seats to achieve this.

As yours has been set up previously, I believe? Follow the replicating camber settings in the guide. Involves remembering to measure the wheel rim to shock body gap before dismantling.
http://www.omegaowners.com/forum/index.php?topic=90652.0
Socket method is far more accurate than anything here.

Re weighting the car, Wim don't bother on this model.  -1.10 is an unloaded figure.

[Shackeng]

Yes I shall be following your guide Chris, sounds a sensible way to check/set, and can be very simply rechecked after running for a while. 

[VXL V6]

Re weighting the car, Wim don't bother on this model.  -1.10 is an unloaded figure.

They used too, they weighted the drivers side on my first two visits to them (many years ago), they also asked what weight is usually carried in the boot of the vehicle.

[chrisgixer]

...but.... For others reading....as camber affects toe if camber is moved, it's by no means a replacement for full geo. the errors are too fine to be measured diy. It can only really be used to minimise wear while the suspension re settles, before full geo set up.

Apologies if that's an overly obvious statement to most here.