How can good ride be stiff ride? December 19, 2009
Posted by richard in : Minutiae of cars , 1 comment so farRIDE, schmide. It’s just about the uncoolest thing in the car world you can obsess about.
But, just as I caught myself wearing socks and sandals while queuing up at the cashpoint last night, so too do I love a nice ride (arf).
What makes a good ride, though? Surely it’s just about soft springs and marshmallows under the wheelarches? Soft = better; it’s a linear and direct connection. Well, that’s what I used to think.
Then I drove the somewhat stiffly-sprung Porsche 911 GT3 RS, and ohmylikeGod fell in love with it – despite detesting it at first, because of an intolerably stiff ride. Utterly inexplicable at the time, it was: me coming back and enthusing over its absorbency, damping quality, sheer depth of talent.
A few years later, I went on my one and only Maserati launch – the Quattroporte GTS. Similar experience; on the taut side, I thought, when I first drove it. Only to emerge at the other end wanting to marry chief engineer Paul Fickers. Luckily, I instead asked him what was going on.
Yet again, the same thing I asked to another chassis top cheese a few weeks ago – and, like Fickers, he said it’s all down to bump steer. See, at speed, it’s not so much the disturbance of ruts on our sensibilities, but the way the car physically reacts to them, that upsets us.
You can have a pretty stiffly set up car, that still seems more than fine, simply because it’s rock-solid assured over even the nastiest of surfaces. This is what the Maser does so well – and, probably, what the Porsche excels in, too.
Chuck in modern cars’ absorption of the nasty harshness that used to so pain us, plus iron-fisted control from decades of damper experience, and you’ve a stiff ride that’s also a good ride. Bizarre but true.
Such as setup also bypasses the other disadvantages of softly sprung cars that made their ride qualities so illusional:
• Roll
• Pitch
• Lean
• Free and easy body damping characteristics
• Uncanny ability to excite toddlers’ stomachs
• The way they suddenly run out of ideas when roads get really challenging
See: Ride CAN be cool. Kinda.
Land Rover’s ride quality secret
Vauxhall gives new Astra suspension a twist
Land Rover’s ride quality secret September 25, 2009
Posted by richard in : Minutiae of cars , 4commentsLAND Rovers all have a characteristic to their ride quality that has to be imparted on all its vehicles, chassis man Murray Dietsch told me.
The secret, he says, is to keep the car level. Not side to side, particularly, but fore-to-aft.
This is pitch. ‘Land Rovers shouldn’t pitch too much – we have a pre-determined rate, that we can get to quite quickly during CAE suspension layouts.’ The trick is to carry this through to real-life machines.
Not easy when you’re dealing with 2.7-tonnes of heavy off-roader, he adds. That’s where the vehicles’ air suspension comes in so handy; now masterminded, he adds, by a tech set-up based on Jaguar’s innovative CATS system.
In practice, this means all Land Rovers have a signature body motion over flowing, undulating roads. The front and rear ends rise and fall at similar rates, to give an almost undetected but exceedingly pleasant sense of satisfaction.
This is something felt all the time – whenever the car is moving, the suspension is working and the pitch rates are being manipulated. But it’s on serious undulations that you can best see it.
Try analysing it, next time you’re out in your car. And, to see what I’m talking about, check out (and feel the Disco lush of) the first half of this video:
Vauxhall gives new Astra suspension a twist
Ride on time August 31, 2009
Posted by richard in : Minutiae of cars , 2commentsIN the olden days, ride quality used to be great on smooth roads.
Soft suspension, coupled with 70-profile tyres, meant it was like riding on space hopper. Rubbery absorption of all you don’t like.
Get the wheels encountering something more challenging, though – such as a rut, or a pothole, or a fag-end, and all holy hell would break loose. Your 1982 Ford Fiesta’s ride quality would show the finesse of stepping off a cliff. One minute it’s OK, the next, it’s having you check the suspension top mounts hadn’t blasted through the bonnet.
Slowly, cars became heavier. And people became less willing to see the side of their Fiestas sink to one side when they got in, because of the overtly-soft settings. Bottoming out when you had the shopping and the kids in the back wasn’t brilliant, either. With an increasing demand for less boast-like handling, so car suspension became stiffer.
For years, car makers puzzled with this. For a while, we had stiffer cars that were now pretty inept everywhere. There wasn’t even the comfort of a chance encounter with new tarmac to make you think it was any good. And, no sooner had they sorted it, when the next model became even heavier. Thus, so it went on.
Now, though, we’re reaching a plateau. Cars aren’t getting any heavier. And suspension dynamics genii have worked out how to make cars pleasing. This means we require a new judgment of what makes ride quality good.
In a few days, I’ll be putting this to the test in a new Renault Clio. See, a while back, I tried the then-new Clio III, and left it with the nuggets of a theory in my head. With the Clio 2009, I’ve another chance to theorise on this, and compare it to both my mum’s rolly old Renault 5, and my quasi-rolly 1993 Clio.
I’ll keep you posted.
Vauxhall gives new Astra suspension a twist
Rover rides with NASA July 2, 2009
Posted by richard in : Technology , 3commentsIT was Rover that introduced the UK to the Pandora’s box of secondary ride quality considerations.
Secondary what? Yes, indeed. Edit the above to insert (non too successfully).
But, there it was. In the 1995 national ad campaign for the Rover 400. Best secondary ride comfort in its sector, didn’t you know.
Rover did bless it up a bit, by headlining it ‘long distance ride comfort’. But you didn’t have to snib that much further to see this mysterious new term mentioned.
What is it? The ability of a car to soak up sharp surface imperfections – you know, high-frequency, low amplitude stuff. Potholes and the like. The noisy, harsh and unpleasant stuff.
As opposed, of course, to primary ride quality. That’s how well a car controls its body motions over bigger road undulations.
Rover did this by using something space-age and cool-sounding: NASA’s official ‘comfort coefficient’ for ride comfort.
Apparently, the Rover 400 had an excellent 2.06 rating. Much better than contemporary Vauxhall Cavaliers, Peugeot 405s, Ford Mondeos and even – get this – traditionally fine-riding motors like the Citroen Xantia and Renault Laguna.
That was in the small print, of course. Communicating this was the canny ‘land speed record’ ad campaign. And, at the time, while few really understood what it was on about, they still remembered it.
If they also remembered something about space, NASA, ride and Rover, then it was job done. Let’s just hope the old HH-R didn’t disappoint too many who were expecting a Rolls-Royce when they got to showrooms.
Because there, they’d discover the interesting revelation about primary ride. That the Cavalier beat it – by its own NASA-sanctioned coefficient, no less. Harsh and knobbly the old Cav 3 may have been (I know – my dad had one), but it couldn’t half control its body motions well.
And the other Rover-beater? The Citroen Xantia.
Whoosh.
A NASA rocket? No, theories about wallowy hydropneumatic Citroens, flying out the window.
BMW X5 – reviewing the 2007 launch
MINI John Cooper S Works Photostream on Flickr
Why Ford Econetics break the rules
