Re: Springs or dampers?
Chris,
Ya never get something for nothing...
I think the 60mm-drop springs are perhaps the culprit but it's too hard to say for sure. 'Both' was the reason as Luke said. I have -40mm springs on my Uno Turbo with new Munroe 'Reflex' (i.e. pretty budget!) shocks. My springs have 'settled' since they were fitted, just with the car sitting in the garage - I haven't driven it for six months and now it looks really low!
Ride quality is a complex subject.
As standard, the ride quality in an Uno is awful
Uno Turbo is kinda OK but if the shocks are worn then it's horrible because it's too soft and 'rocks' from side to side! All Unos are a bit flexible IMHO meaning a big shake of the dashboard when you hit something in the road. I can only imagine this getting worse with harder suspension - nothing you can do about that.
You've probably got some bigger alloys with low-profile tyres. That is going to make the road noise louder and the ride more sensitive to the 'texture' of the road. However it's also going to reduce that 'spindly', wandering feel of Unos on 145 tyres... so in my books that makes the ride quality better.
As Louie says, the design of the seat makes a difference. Softer is not necessarily better since you don't want to be rolling around (ever driven an Austin Princess? or any other 70's BL car? THAT's how bad seats can be!)
Shock absorbers, particularly shock absorbers that are stiffer than normal in order to cope with stiffer springs, are going to make the ride more 'choppy' - more sharp displacements - but they are also going to reduce the diving when you brake or the lifting when you accelerate, and you won't 'float' over bumps during cornering. Thus, that's all going to improve the ride quality in some sense even though it feels more choppy.
Springs - lowering the centre of gravity reduces the roll during cornering which, for the passengers in particular, is more comfortable. Yet of course the decreased suspension travel means that the spring has to be stiffer to prevent bottoming-out. Thus when you hit a bump, the spring won't deflect as far as a standard spring, meaning that the bodyshell will take some of the impact and you'll feel it.
On a lightweight car like the Uno, something called the 'sprung/unsprung mass' comes into effect. The unsprung mass is everything that moves when a wheel hits a bump: the wheel itself, the brake assembly, the suspension arm, and the strut. The sprung mass is everything else. Cars like the Uno have relatively lightweight suspension/wheels, but the bodyshell/engine etc. is also lightweight. This means that when the unsprung mass moves (hitting a bump) the sprung mass starts to move too (transfer of momentum).
Cars like the Austin Allegro were particularly bad because the suspension was made out of heavy cast-iron and the gas/liquid springing was under-damped (have you experienced the bouncy ride?)
Ever noticed how a Rolls Royce, or a Bristol, or a Mercedes, weighs a lot more than the 700-845kg of an Uno? That's the basic ingredient of their smooth ride, not just softer springs or dampers. In fact, just about any newer car weighs more. That allows the sprung mass to be proportionately more than the unsprung mass, particularly with BMW's aluminium suspension - the goal of that is to reduce the unsprung mass and therefore improve the ride quality. It's expensive, but it works.
Now on the other hand YOU have probably increased the unsprung mass of your Uno - by fitting bigger wheels. So, you can't possibly hope that the ride quality will improve
Of course ride quality is a subjective issue. The engineers at FIAT tried very hard for the best compromise (and not just to save money: it cost them a lot to fine-tune the spring and damper rates) so you can't really hope to improve on the compromise overall. However, you can move the compromise towards your personal preference. I would prefer my Uno to feel glued-to-the-road at all times with plenty of stability and feel in the steering, even if it means that the ride becomes less smooth. That's because the ride was never smooth to start with, compared with bigger cars... so why try to preserve it?
If in all this you were looking for an answer to your question - yeah, try the 35mm springs, if they still fit... and you'll need another wheel alignment so more expense
Make sure that your Uno doesn't handle dangerously, i.e. check for how the steering responds if you encounter a bump mid-corner, make sure the car is not bouncing as you drive down the road (because that could reduce tyre grip), and also be aware that handling 'on the limit' probably gives you less advance warning (understeer) than it used to, so know the warning signs before you spin... Unfortunately all these things begin to occur as you go lower and stiffer, particularly if (for some reason) the shocks are not stiff enough for the springs.
I see that I've written heaps on my 'complex subject', oh well, probably no-one will read it
I've wasted a great deal of time adjusting suspension on a particular car (my FIAT 128 Coupe) and I know that sometimes it was overall worse than standard. It really is a world of compromise, the 'standard' settings are sometimes the best, and only you can decide what is important if you stray from those.
-Alex
