RE: PH Blog: passive / aggressive
Discussion
Palmball said:
wormburner said:
These systems that gradually ease back from 'sport' to 'standard'... at what point does the 'sport' light go out?
If this was happening surely people would be heading back to dealers to say their car won't stay in sport mode?
It doesn't....the light stays on so it 'looks' like its still in sport (assuming systems actually do in fact do this). If this was happening surely people would be heading back to dealers to say their car won't stay in sport mode?
Greg 172 said:
wormburner said:
These systems that gradually ease back from 'sport' to 'standard'... at what point does the 'sport' light go out?
If this was happening surely people would be heading back to dealers to say their car won't stay in sport mode?
As I understand it (from my seemingly poor memory of an article), when you press the 'sport' button the dampers change to a firmer setting and remain there - they don;t go back to standard ove time. It's just that it gives you a couple of miles (or whatever) of additional firmness to confirm to your senses that you're in a sportier mode.If this was happening surely people would be heading back to dealers to say their car won't stay in sport mode?
For a VERY simple example, something like this:
Standard damp rate = 100%
Sport damp rate for first 2 miles after button pressed = 160%
Slacken back to actual sport damp rate = 120%
Hope this makes sense, these are just figures plucked from the air, using 100% as 'average' firmness.
Maybe someone more techy can give a more accurate explanation?
wormburner said:
Thanks, that makes some sense. Though I can't help thinking there might be some liability issue if a crashed car is shown to have been gradually altering its driving characteristics outwith the knowledge of the driver.
I'd argue that those alterations would have to be fairly drastic and would have to be detrimental to the car's handling for there to be a case.ETA - A car's handling changes significantly all the time, even on a 'passive' car. Tyre pressures change, and dampers have variable performance depending on temperature and amount of work they're doing.
Edited by The Wookie on Thursday 10th May 14:18
The Wookie said:
wormburner said:
Thanks, that makes some sense. Though I can't help thinking there might be some liability issue if a crashed car is shown to have been gradually altering its driving characteristics outwith the knowledge of the driver.
I'd argue that those alterations would have to be fairly drastic and would have to be detrimental to the car's handling for there to be a case
ks.Certainly I'd imagine the manufacturers might think "this is a problem we don't need to give ourselves".
hygt2 said:
jackal said:
Switchable dampers will be more relevant when we have switchable springs surely ? Chassis tuning starts with changing the springs and then altering the damping to suit. Changing single way damping settings at the same constant spring rates is fairly limited in its useage ime. Firming up dampers really hard without firming up spring rates also just feels plain wrong.
That said, i wouldnt want to be without the settings in my cayenne, im forever swtching between comfort and sport depnding on my mood and what sort of driving im doing.
Does your car have switchable air-sprung as well as having switchable dampers? That would be great to have.That said, i wouldnt want to be without the settings in my cayenne, im forever swtching between comfort and sport depnding on my mood and what sort of driving im doing.
Edited by jackal on Wednesday 9th May 17:43
wormburner said:
I'd agree, but I'd say a good brief might be able to ask enough good questions along the lines of 'what is 'sport mode' and why would I need it? to make it an interesting exchange. I don't think it'd have to be detrimental to handling, just different, wouldn't it? And it'd be unarguably 'different' otherwise they'd have to admit it's all bks.
Certainly I'd imagine the manufacturers might think "this is a problem we don't need to give ourselves".
Perhaps, but I suspect if there were an issue then there would be a clause in most cars' handbooks that says something wishy washy like 'caution: car behaviour will change, adjust your driving accordingly' if there isn't already. ks.Certainly I'd imagine the manufacturers might think "this is a problem we don't need to give ourselves".
I suspect manufacturers have already thought of it judging by the common instrument pack alerts that accompany pressing the button. I think virtually every car I've driven with such a system (even dating back to the late 90's) has a light or a suspension pictogram on the display that appears when the button is pressed.
It's an interesting point though.
The Wookie said:
wormburner said:
I'd agree, but I'd say a good brief might be able to ask enough good questions along the lines of 'what is 'sport mode' and why would I need it? to make it an interesting exchange. I don't think it'd have to be detrimental to handling, just different, wouldn't it? And it'd be unarguably 'different' otherwise they'd have to admit it's all bks.
Certainly I'd imagine the manufacturers might think "this is a problem we don't need to give ourselves".
Perhaps, but I suspect if there were an issue then there would be a clause in most cars' handbooks that says something wishy washy like 'caution: car behaviour will change, adjust your driving accordingly' if there isn't already. ks.Certainly I'd imagine the manufacturers might think "this is a problem we don't need to give ourselves".
I suspect manufacturers have already thought of it judging by the common instrument pack alerts that accompany pressing the button. I think virtually every car I've driven with such a system (even dating back to the late 90's) has a light or a suspension pictogram on the display that appears when the button is pressed.
It's an interesting point though.
After all, if it isn't important or relevant to the driver to know for certain which mode they're in, for reasons of vehicle behaviour (and ultimately, safety), why is it flagged-up with a light on the dashboard?
The Wookie said:
I'd argue that those alterations would have to be fairly drastic and would have to be detrimental to the car's handling for there to be a case.
ETA - A car's handling changes significantly all the time, even on a 'passive' car. Tyre pressures change, and dampers have variable performance depending on temperature and amount of work they're doing.
This has just reminded me of the clack clack noise that the original Koni dampers on a S1 Elise make when they've had a bit of a work out. ETA - A car's handling changes significantly all the time, even on a 'passive' car. Tyre pressures change, and dampers have variable performance depending on temperature and amount of work they're doing.
Edited by The Wookie on Thursday 10th May 14:18
wormburner said:
Aye. I don't think it's a big deal. It just seems slightly risky from the 'silly-litigation' POV to build a car that an untrained driver can 'tune' on the fly, which then quietly and seamlessly, slowly disregards what they summoned of it.
After all, if it isn't important or relevant to the driver to know for certain which mode they're in, for reasons of vehicle behaviour (and ultimately, safety), why is it flagged-up with a light on the dashboard?
I think it's a fair point when it comes to the huge adjustability available on something like a BMW M3 or M5 for example. All those different permutations, who knows if a mid corner gearshift in a setting one step more aggressive than what the owner usually uses would be enough to unsettle the car?After all, if it isn't important or relevant to the driver to know for certain which mode they're in, for reasons of vehicle behaviour (and ultimately, safety), why is it flagged-up with a light on the dashboard?
The likelihood is that every manufacturer would have tested every permutation possible to utter exhaustion and will have documented it thoroughly, and that is what they will fall back on should they be challenged.
I think the premise of 'as long as it's not dangerous' is evidenced by the fact that on most non 'driver oriented' cars the ESP cannot be fully switched off. I've driven quite a few common and well regarded cars that demonstrate some fairly dodgy and suprising handling characteristics with the electronic aids disabled.
Dan Trent said:
Jaguar has been watching the thread and, FWIW, I've been told that this is absolutely not the case with its adaptive damping system. For the record, etc...
Excellent...then I am happy to tell them that I'm delighted by how my new XKR drives...it's body control on our typical bumpy/broken/rough roads is exemplary. No better than a good 997 maybe but then the Porsche doesn't have anything like the ride and refinement of the Jag (if that's what you want...I appreciate that many don't). So, I will bow to their obvious expertise and accept my car does have permanently different damper settings In Dynamic mode but, I can't get away from the feeling that it definitely feels perceptibly harder immediately after selecting Dynamic and this extra firmness subsides afterwards. Now, this could just be me getting used to the firmer setting thereby not noticing it after a familiarisation period (very possible given I thought the 911 had a similar characteristic) or, by the very nature of it constantly varying to the road conditions, maybe it 'learns' what the car is doing after a while and then settles down (pretty much as Greg 172 suggested in that it slackens back to a softer, yet still 'firmer' setting). Ahh who knows (except Jaguar)...all I can say is that it works and I like it.
And whilst I have Jaguars attention
.....you could improve the experience further by: 1. A nicer (read: a bit smaller, a bit thicker and with thinner spokes) steering wheel. The XKR-S at least should have such a wheel (mine isn't a full blown -S but it does have the -S suspension set-up in the form of the factory dynamic pack so this should include it too
)2. A rev counter that is useful...in manual, the car can smack into the limiter before it gets anywhere near the redline meaning you can't drive it with rev perfect precision. Either the dial's inaccurate or it can't keep up with the motor.
That's it chaps and apologies for going waaaay off topic....couldn't resist
wormburner said:
So what happens when you switch back to 'standard', nothing except the 'sport' light going out?
See above...according to the horses mouth, it is in a different Dynamic setting so thereby reverts back to a more comfortable setting (not that you notice it much but it does unfortunately quieten the exhaust, soften the gear changes and, most importantly, turns the light off )Johnboy Mac said:
rtz62 said:
The late, great LJK Setright would spin in his grave at these tricky-tracky adaptive dampers.
He was a man who loved pure engineering, and would have described adaptive suspension as a smokescreen to disguise the inadequacies of the chassis engineers...
Reading that made me smile - I reckon you're right, that's exactly what LJK would have said.He was a man who loved pure engineering, and would have described adaptive suspension as a smokescreen to disguise the inadequacies of the chassis engineers...
No mention of tyres Dan? the oft overlooked part of the suspension 'system'... Just look at how wheel sizes and tyre profiles have changed over the last ten years.
Personally I definitely think there's a place/future for adaptive dampers. Just look at your Five; I wouldn't use the Propedal on a daily basis, but faced with a half hour fire road climb, I sure as sh!t would turn it on. For a performance car I'd happily take a set of dampers that were biased towards road use but you could firm up the low speed compression for track days.
Personally I definitely think there's a place/future for adaptive dampers. Just look at your Five; I wouldn't use the Propedal on a daily basis, but faced with a half hour fire road climb, I sure as sh!t would turn it on. For a performance car I'd happily take a set of dampers that were biased towards road use but you could firm up the low speed compression for track days.
Edited by Danny Milner on Thursday 10th May 22:24
I'd like to have a go in one of these MX5s with perfectly set up suspension.
Ideal for motorways, B roads, gravel, off roading, pot holed roads, speed bumps, track days, sand, mud, rock crawling...
Come to think of it, why don't the army use MX5s like this? Far cheaper than an Chieftan tank and more capable!
(I'll stick with the PASM in my Boxster thanks. I know how it works, I know it works, and I know it's great for track days and the very occasional B road blat. As another user has pointed out, these things work over a range of "firmness", it's not "hard" or "soft" unless they're cheapo knock off kits, the difference in the setting is the speed they're allowed to respond to varying road and driving conditions, and the range they operate over.)
Ideal for motorways, B roads, gravel, off roading, pot holed roads, speed bumps, track days, sand, mud, rock crawling...
Come to think of it, why don't the army use MX5s like this? Far cheaper than an Chieftan tank and more capable!
(I'll stick with the PASM in my Boxster thanks. I know how it works, I know it works, and I know it's great for track days and the very occasional B road blat. As another user has pointed out, these things work over a range of "firmness", it's not "hard" or "soft" unless they're cheapo knock off kits, the difference in the setting is the speed they're allowed to respond to varying road and driving conditions, and the range they operate over.)
Silent1 said:
Did anyone else find this article oddly hard to read, it felt like it didn't really have any flow to it?
Also parts of it read like an absolutely blatant advert.
As for adaptive dampers, they are trying to create magnetorheological dampers without having to actually do the research/spend the money on it.
IIRC in this country only Audi and Ferrari have fitted them to production cars (the TT, R8, 458, 599GTB and the F12) and the road going versions are still not the full package compared to below.
To see how good 'adaptive' dampers can be, watch this and then tell me that passive dampers are still better than them and that the chassis is the be all and end all of it!
If that link doesnt work, watch this video from 5 minutes 59 seconds onwards for the actual demonstration:
Click here
No you're not alone. I'm not keen on matey's articles if I'm honest. Is he a GCSE student?Also parts of it read like an absolutely blatant advert.
As for adaptive dampers, they are trying to create magnetorheological dampers without having to actually do the research/spend the money on it.
IIRC in this country only Audi and Ferrari have fitted them to production cars (the TT, R8, 458, 599GTB and the F12) and the road going versions are still not the full package compared to below.
To see how good 'adaptive' dampers can be, watch this and then tell me that passive dampers are still better than them and that the chassis is the be all and end all of it!
If that link doesnt work, watch this video from 5 minutes 59 seconds onwards for the actual demonstration:
Click here
Edited by anonymous-user on Wednesday 9th May 22:15
otolith said:
Johnboy Mac said:
rtz62 said:
The late, great LJK Setright would spin in his grave at these tricky-tracky adaptive dampers.
He was a man who loved pure engineering, and would have described adaptive suspension as a smokescreen to disguise the inadequacies of the chassis engineers...
Reading that made me smile - I reckon you're right, that's exactly what LJK would have said.He was a man who loved pure engineering, and would have described adaptive suspension as a smokescreen to disguise the inadequacies of the chassis engineers...
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