Suspension Settings

[Nero]

Hello,
I have a big problem with rattings in the road. The europa want to pull in them. It’s simply dangerous to drive fast then 80kph. The front suspension is original apart from coilovers and a upper arm to give camber adjustment. The car is on 185/60 13 tyres in the front. We already changed for new tyres as we suspected old tyres to contribute to the problem. The suspension settings are as per the workshop manual. From driving I can say that it is definitely from the front. I increased the toe in at the front already with next to no difference.
If somebody with the same or bigger tyres could give me their settings I would really appreciate it.

Thanks
Denis

[jbcollier]

Have a computerized, four wheel alignment.

- if the included angle (AKA: kingpin inclination/KPI) then the uprights are bent.

- rear thrust angle also important.

I'm suspicious that something might be bent if you have adjustable front upper arms.

[EuropaTC]

As John says, the first stage is to get 4 wheel alignment done to get a known baseline before modifying anything.

I have 195/50 & 205/50 tyres on a TC car but with adjustable suspension so perhaps my settings won't translate to your car.  Even so, they are broadly in line with the OEM settings and I aim for mid-range on toe settings, low end on rear camber. The ride height is also slightly lower than OEM. Front camber isn't adjustable on my car so I hope it's standard ! 

The image shows the details recorded almost 4yrs ago and with a mixture of imperial & metric numbers but this was the last time I made any changes. I seem to recall moving the OSR toe closer to the NSR toe after this measurement going on the noted shims, but memory.....

When you say it's unstable at moderate speed, what's the effect ? is it vibration or the car responding violently to bumps, road camber, etc ?  If it's definitely the front and your toe is within range then I'd look to see if there's anything wrong with the steering gear, maybe that coupling hidden in the chassis, the track rod ends, bearings, etc.

Brian

[4129R]

I would also check:-

1) Tyre pressures and uneven tyre wear.

2) The bottom trunnions are working properly.

3) Any movement in the rubber bushes.

4) The top wishbone arms are the correct way around. Thick one at the front.

5) Wheel bearings.

6) Steering rack.

I don't understand "rattings". Do you mean the thick white lines on the tarmac, the camber of the road, the grooves in the slow lane made by heavy lorries, or potholes in the road surface?

[Nero]

Thank you guys.
For better understanding: groves in the road are problem. Potholes are not more of a problem as with any other car. The car obviously gets pull in them when they are to big.

The car just got completely restored and has about 400km on it. All of the bearing and bushings are new, so I don’t suspect them to be a problem. In the corners the car is absolutely amazing(as a europa should be) so I don’t think there is something totally wrong with the suspension. The steering rack is fine, we just took it out to check. The car is very direct to the steering, actually to direct, but I never expected anything else from this kind of steering geometry.
The tyre pressures are the next thing to check and then the alignment.

Thank you for your input
Denis

[jbcollier]

My restored car had all its original front suspension components.  They looked great, with no sign of damage.  My brand new bushings delaminated within 100 kilometres resulting in the front arms being pushed backwards.  After I fixed that -- bushings must have rolled edges -- I had the alignment checked.  Both front included angles were off so both seemingly fine uprights were bent.  And, the rear thrust angle was off by quite a bit.

Don't rely on "looks" and "feel".  Check it out properly!

PS: If your camber is off, don't reach for adjustable arms, find out what is bent or worn.

[4129R]

The stickier the tyre, the more that lorry grooves pull the car and as the lorry track is wider than cars, that can lead to problems.

Try driving a car on roads with dry racing tyres and the white lines cause a problem.

[Nero]

The car is running on sticky tyres simply for the reason that it is hard to find tyres in 185 and 205 for 13“ wheels that a road legal in Germany and without paying a fortune. The old ones were pretty much the opposite of sticky but the pulling was the same, that is the reason why the tyres got changed in the first place.
The car popped a heater hose this weekend so there are other things to do before the alignment can take place. I will report back as soon as I have news

[Pfreen]

Hopefully in the engine bay and not under the dashboard.

[Clifton]

The car is very direct to the steering, actually to direct, but I never expected anything else from this kind of steering geometry.
The tyre pressures are the next thing to check and then the alignment.

 I've had light weight road race and autocross cars and run toe out and they don't feel as twitchy as my Europa at speed.  2 hands over 80 mph. 

My specs, I am running super sticky R comp  BFG Rival S tires. 205-50-15 in the front, 245 rear. I don't remember what my front camber is (slotted uppers) or caster, I shimmed it to get another half degree but the front is toed in a heavy 1/16".  Rear camber - .75*  but it is not Europa in the rear, rear toed in is 1/16". I tried an 1/4" toe in on the front and it made it worse.  Thrust is perfect.  I will increase rear toe in to 1/8" next and see if I can get more caster. I car with too much toe in wants to wander and not return to center very well after turning unless it has a bunch of caster. A toed out car turns in great but will follow cracks, grooves, paint stripes, seams ,ect much worse.

Are you100% you are not toed out or too close to zero?

[Nero]

Hopefully in the engine bay and not under the dashboard.

Luckily in the engine bay. My father made a crossover pipe because we didn’t want the hoses laying on the engine.The hose slipped of that pipe.(see picture below)

Are you100% you are not toed out or too close to zero?

We initially set the toe in to the lowest within the factory spec. So it is toe in but not that much.

[Pfreen]

Nice looking engine.

[Nero]

My father had the alignment done last Friday. The king pin inclination is perfect in spec. The toe in on the front is 1.3 degrees to each wheel(2.6 in total) which is actually good. The caster in the front is only .5 degree. Camber is good. On the rear the toe is just slightly towards toe in(.5 degree).
First I want to get the caster within spec as it affects straight line stability a lot.

[jbcollier]

That is not enough toe at the rear.  Europas are quite twitchy with minimal rear toe.  The rear toe setting in the manual is per side, not total as in the front.

If your castor is off, something is bent.

What was your rear thrust angle?

[Nero]

We already adjusted the toe on the rear as the car runs with a 47 replica chassis, which means the adjustment is towards the rear of the wheel and that makes adjustment a fast and easy process. My father made the jig for the adjustable upper arms over 15 years ago, which means I need to look at the drawings to compare them to the factory ones.
I need to have a close look at all the parts because there are too much variables within the front suspension right now.
I will look at the rear thrust angle tomorrow as it is late in the evening right now in Germany.