Should smaller wheels with higher profile tyres become an option for the UK. And would longer travel suspension as used to be favoured by the French help with damper calibration? (jerry99)
This question sounds like this may well be a ‘soap box’ of yours – not to worry, it’s one of mine too. Indeed the wheels and tyres on my previous vehicle accounted for over 100kg and, including their inertia, increased the effective mass of the vehicle by over 13 per cent.
Unarguably, the main driver for both low ride height and big wheels is vehicle styling, but from a ride and handling viewpoint there are lots of reasons to stay away from both. However, some of the younger chaps in Prodrive’s chassis department find the lower cornering stiffness of higher profile tyres difficult to accept. I guess that means while most dynamics engineers would welcome cars with smaller wheels with higher profile tyres, the high/low profile discussion is less clear cut.
I don’t think anyone argues against long travel suspension, but there are many reasons why it can be difficult to achieve. For example: pedestrian impact requirements necessitate lower front strut towers;, styling often likes a lower bonnet line; and good interior volume – in the boot for example – is more important to many people than ride.How does the road surface impact on road noise? I always notice heading off the Eurotunnel at the French end that there is less road noise, and my car seems comparatively quiet, why is that? Some cars (notably Japanese) seem to shout unacceptably loudly on UK roads. Is that the road, the car design - or just the tyres that need to be improved? (Big S)
Road surface has an enormous impact on road noise. Noise is a vibration and the vibration in a car is pretty much generated by two things: the road and the engine. The engine generates a pretty consistent range of excitation whereas the road is incredibly diverse.
As for the Eurotunnel experience – it’s difficult to say. In part, I’d say you’ve probably not long left the M25 on the UK side and so, by the time you’ve reached the ferry, the tinnitus from the dreadful Southern section hasn’t quite subsided. On the other side of the tunnel the roads are pretty good.
Is it the road, cars or tyres that need to be improved? All three influence the noise in probably equal measures and, to be fair, all are improving with time. If road noise irks you, then you could do well to play with the tyres on your car. That sounds expensive – and it is – but I’ve blessed eBay with some nearly new tyres on more than one occasion because they weren’t to my taste.
Is the low noise, low spray, high quality tarmac that one comes across only occasionally in the UK made from recycled glass? (Chuffy)
Bah! The embarassment – I have no idea.
Are oleomagnetic dampers the way to go or will active ride return in some form to improve ride? (Pagani1)
Generalising, there are two camps for adaptive damping in whatever guise. The first is in the luxury end where the adaptive dampers are fitted in order to keep the vehicle competitive and the cost is swallowed in the ticket price: Jaguar XJ, BMW 7-Series, etc.
The second is where the dampers are fitted as an option that the customer pays for. In the latter case, there is a trap. If the customer is to pay, then there’s usually a need for a switch to show he has the system. If there’s a switch, then there’s a need for the switch to make a noticeable difference.