The old adage that goes if you build a better mousetrap, the world will beat a path to your door is frequently attributed to Ralph Waldo Emerson, but what he really wrote was If a man has good corn or wood, or boards, or pigs, to sell, or can make better chairs or knives, crucibles or church organs, than anybody else, you will find a broad hard-beaten road to his house, though it be in the woods.
People are seemingly always looking for that elusive better mousetrap, because apparently everybody in the world hates mice. Maybe the world’s engineering minded could have tackled the whole rodent rubout issue if their time wasn’t seemingly taken up with the inscrutable issue of perfecting automotive suspensions. You see, while mechanisms to hold up either end of a car were devised all the way back at the dawn of the automobile, the slide-rule folks have been tinkering ever since trying to find a better way to do it.
Much like the branches of the evolutionary tree, many of those have been dead ends. What I’m interested in today is your opinion on which of those you think got the short shrift. What do you think was the best suspension design that never really caught on?
Image: P6Club.com
Hooniverse Asks: What's the Best Suspension That Never Really Caught on?
By Robert Emslie
Jul 29, 2015
Jeff Glucker
Rear suspension employing a transverse composite leaf. While it did catch on initially as a holdover from the buggies from which the first horseless carriages were built, in modern cars, it has largely gone ignored, despite weight and packaging advantages.
I believe only the Corvette and Volvo 960/S90 have used one in recent times. However, in looking into this topic for my response, I found out that Volvo is employing one on the new XC90:
http://blog.autoworld.com.my/wp-content/uploads/2014/08/volvo-xc90-transverse-leaf-spring.jpg
The C7 uses them front and rear. It always pissed me off that the guys on TopGear would sneer at them, calling them pram springs.
If one of the world’s top performance cars uses them, I think they need much broader deployment!
Am I correct in thinking that they can function as anti-sway as well as load-bearing, or am I imagining the physics and mechanical engineering at work here?
So what’s the downside, preventing more widespread use?
They are difficult to package as they require a clear path from hub to hub, as well as significant room to displace. Also they are expensive to buy if you wish to change rates, and it’s difficult to adjust ride height, hence why many track Corvettes are converted to coil-over setups.
They do have many advantages though, as enumerated above. A solid choice for a factory suspension design.
Excellent, thanks! Leroooys link below tells of some (minor?) height and balance adjustment possibilities – maybe that’s a fix for one issue?
The C7 Corvette continues on with a transverse composite leaf spring (yellow) that presses against the lower control arm.
This height adjuster (green) is a nice feature of this layout, and a Corvette has one at each corner. Twirl all four and you can lower the car. Tweak selected ones while the car is sitting on a set of digital pad scales and you can “corner weight” the car to evenly distribute your own mass or optimize the car to suit whatever track or autocross course you might be tackling.
Sounds like an overwhelming job to convert a car’s suspension just to lower it…
Yep, the C7 has some limited height adjustment built in. It’s a cool design, the only downside being that it affects spring preload (as do many less-expensive adjustable coilovers).
In the conventional mounting, they do not act as anti-sway components, as anti-sway bars are defined as acting solely in roll with the heave action unimpeded. They can, however, act as heave-only elements if mounted via pivot, which gives other dynamic benefits (by separating the heave and roll elements).
There’s a great writeup of it here:
http://www.edmunds.com/car-reviews/track-tests/2014-chevrolet-corvette-stingray-z51-suspension-walkaround.html
I love this guy’s suspension walkarounds, though sadly they seem to have become defunct. Enjoy it while the pictures last!
The 90’s -era GM W-body cars employed a composite transverse monoleaf, if i’m not mistaken. I couldn’t find a picture of it, and I’m not so bright with these things, so maybe that’s not exactly what you’re referring to here.
The Brazilian Fiat Uno had transverse leaf spring too
http://2.bp.blogspot.com/-5rlRIO2uaEc/TlV66ILGbxI/AAAAAAAAAmc/l_88GbrJFkk/s1600/Turin%252C%2Bboa%2Be%2Bbarata%2Bsusp.%2Btraseira%2Bindependente.jpg
Any number of Citroen setups, but most notably the zero roll design created before the SM, but not produced until the Xantia Activa of 1994.
http://www.citroenet.org.uk/miscellaneous/hydraulics/hydraulics-2.html
This desperately needs a dance beat.
http://www.citroenet.org.uk/miscellaneous/hydraulics/images/activa.gif
Okay, let’s, um, make this part longer, and use an arm here…and put the spring up there, so that the, uh…spring can be up there!
http://www.aronline.co.uk/images/p6dev_01.jpg
That’s a great P6 drawing that I don’t remember seeing before. Cocktail napkin? That front suspension was a pain as far as sourcing shock absorbers in the Rover-neglected USA. If you look at this drawing and the one at the top of the page, you can see that the shocks have to be valve in reverse since they lengthen as the spring compresses and shorten on rebound. The rear suspension of the P6 is a modified De Dion setup which kept the wheels perpendicular to the road as they moved up and down in the wheel well. I drove a 1970 Rover 3500S from Wichita to Philadelphia once in the early 90’s. Although the car had seen better days, it would always take a “set” in high speed corners and just swoosh through them better than the modern designs around me on the road. And the ride was great, as well. The Rover was an extremely refreshing clean sheet design that was quite daring for a small company. It was intended to be powered by a gas turbine engine, and a prototype turbine car was built and operated. I believe it is in Gaydon with the Rover-BRM Le Mans turbine race car.
The spring location does put a lot of road noise into the bulkheads. P7s, (The six cylinder version of the P6) and P8s, (‘ the would have been big brother’ 4.5 litre companion to the P6) both were designed with a sub-frame mounted double wishbone set up. But they all kept the ‘no camber change’ De Dion rear suspension which was also used by Alfa Romeo and Aston Martin.
Remaining damaged P8 prototype as stored very badly at Gaydon.
http://www.aronline.co.uk/blogs/wp-content/uploads/2012/10/6thOctober20122640x480.jpg
Amazing the museum would store a prototype that way.
The other side of this technical sophistication issue was the SD1. It had a good though much less sophisticated rear suspension due to financial constraints but handled like an MGB. When taking freeway off-ramps at unreasonably high speed, it left the P6 behind. “Raced” a couple…
But they don’t have nearly as good a ride – which of course doesn’t mean anything nowadays. Where handling on a racetrack is considered more important. I prefer a modified P6 to the SD1
True. I’d prefer a P6 as well, and a 2000TC to the 3500S we got in the USA. Plus the build quality of the American market early SD1s was abysmal – both materials and assembly. But it did look like a five-passenger Ferrari Daytona if you squinted just right. Given the resources they had to work with after being taken over by BL, they did a respectable job, and the Series 2 cars in Britain appear to have been much better.
I would disagree on this from experience in the opposite (P6 v. SD1) camp – most SD1s (with the exception of the diesel) will typically outrun the equivalent P6, but if the P6 driver knows exactly how hard that car can actually be pushed in the bends, it will ultimately outcorner the SD1.
That’s not to say that the SD1 handled poorly; it didn’t. But there were certain advantages to the P6 that weren’t inherited by the SD1.
Of course, this could easily turn into a Ford v. Chevy, Mac v. PC, or other polarised argument with zero effort. I’ll just make my P6 bigotry clear and leave the floor open.
Not all P6’s in the Rover parts-starved USA were always in the best nick in terms of bushings and dampers. My SD1 had some upgrades (just a couple) and was somewhat “basic” but it held the road very well and could be tossed quite a bit. I think a properly sorted out 2000TC would be the best US-spec P6 and better than the US-spec SD1s. A friend has a 2200TC he imported from the south of France, and it’s really something with some well thought out detail improvements. (Except for the hood and the plastic grille.)
Fair points, and I’ve only ever driven one US-spec SD1. To me it felt tired, but that’s not surprising given that it was already almost 20 years old when I drove it and had clearly not been the beneficiary of maintenance in quite some time.
That said, the last SD1 I had driven before that was a 2400 diesel, and, well, wasn’t much different in terms of maintenance. I have driven both the 4- and 8-cylinder cars in better shape, though, and would love to have been able to draw a direct comparison with them against the US V8 models to see what the real differences were between the two.
As regards the 2.2-litre P6s: I’d honestly rather have a 2-litre car. The 2.2 is definitely the more advanced and powerful engine (and I’ll fully admit that 2000s are somewhat agricultural), but for durability the 2.0 will typically outlive them.
I’ve owned quite a few 2000TCs and my favourite was a US spec NADA
2000TC with the 10:1 CR engine that had been brought to NZ by an
American serviceman serving with the US Antarctic Service, Operation
Deep Freeze.It was faster than my first few P6Bs. And with Koni shocks
and a KMac rear antiroll bar and good tyres it handled quite well,
better than the later V8s with their shorter front suspension arms.I do
plan to get some more P6s in a few years time- they do seem to be
staying quite affordable.My memories of SD1s are always coloured by the
memory of the first one I sat in in the showroom and the seat lining
fell off on my knees. On a brand new car. but they’re quite affordable too.
Agreed on the noise into the bulkhead – I used to have a P6 (2000 Automatic), and at certain speeds you could hear the noise from the front wheels being channeled into a spot right in front of the doors.
If it’s any consolation, when I had that car 20 years ago in the UK (and later Ireland), shocks were already hard to come by. There were a couple of people who would rebuild them, but you’d wait for weeks to send yours in and receive them back.
And yes – that is a *fantastic* drawing! I’d love to know the source of it.
That drawing is a sketch by Gordon Bashford of Rover’s engineering section and is often shown with one of his other sketch showing the rear suspension layout of the P6
http://www.aronline.co.uk/images/p6dev_02.jpg
They date back to the late fifties when the car was perhaps going to look this
http://www.aronline.co.uk/images/p6dev_14.jpg
or this
http://www.aronline.co.uk/images/p6dev_08.jpg
And the first prototype Note the DS Citroen-like frameless glass which wasn’t continued with. Though the P6 does have a similar drag coefficient to the early DS.
http://www.aronline.co.uk/images/p6_10.jpg
And the prototypes soon looked more familiar like this, the seventh one, badged as a Talago
http://www.aronline.co.uk/images/p6dev_11.jpg
Pictures from AR Online http://www.aronline.co.uk/blogs/concepts/concepts-and-prototypes/projects-and-prototypes-rover-p6/
And Gordon Bashford, Spen King and Jim Randle with the first two P7 prototypes after brake testing in the Alps. Jim Randle later Head of Engineering at Jaguar, Spen King,’father’ of the Range Rover.
Sure it’s likely way too expensive and finicky for what Lexus would want, but a company like Jag isn’t worried about log-term durability, they could brig it to market.
This is fantastic — I remember reading about it in Pop Mech many years ago, then saw the video and it reminded me of an equestrian agility contender leaping over the fence obstacle.
I think the hydropneumatic suspension in the Citroen DS was pretty neat. Jay Leno did a cool video of his and demonstrated how it worked.
Not just on the DS, but all hydropneumatically suspended Citroens like my BX and CX, and later Xantias and XMs and C5s and C6s.
Somehow Citroen’s new DS range is supposed to reference these cars and fails badly with a quite noticeably poor ride and yet not very good handling- like an ’80s Audi 80 nonQ.
Because they have dropped Citroen’s USP and failed to come up with anything as good but the cars are now cheaper to make – just what your expensive/luxury car buyer wants to hear.
‘The cars not as good as it could be because we cut costs to make more money, but we’re still charging you more for it.’
What an excellent video. One point he missed was that every body panel (including the roof) could be simply unbolted for replacement, a feature it shared with the later Rover P6. On the P6, even the sills unscrew and come off to let you inspect the base unit.
I drove a modern DS as a vacation rental once. The steering was directionless and scary, the ride nothing remarkable. Two letters might not make a name, but I still think Citroën does abuse the tag wildly.
The 1988 Nissan Maxima had an option called the “Sonar Suspension” which in theory “read” the road surface by means of sonar and sensors, then adjusted the shocks accordingly for the best ride. I’m not sure how well it worked.
Wow, new to me. Sounds way to advanced for 1988. How is the sonar/sensor-information being processed?
Sausage grinder.
Fuzzy logic!
Wasn’t that the required answer for any Japanese electronics from the late ’80s/early ’90s?
The chassis hardware would have been the bottleneck. It would need modern MagneRide-level components to respond quickly enough to be useful.
It would be interesting to have GPS based adjustment of baseline suspension settings, like BMW’s GPS transmission inputs. The US interstate highway system is 50K miles; an inch by inch ground map of three lanes (avg) for 50K with simple 1988 Maxima-type sensors certainly is practical. If you expand that to the 100K or 200K most traveled miles in the country, that’s still pretty practical. When a vehicle isn’t on a surveyed travel lane, you could make generalized settings any way you want; county by county, zip code by zip code, two lane, four lane, unpaved, etc.
To make it really crazy, the fleet of GPS suspension cars could continually report back on road surfaces to expand coverage and update the system’s information.
Paging Mr. Goldberg to Engineering! That would be a painfully complex way to do something unimportant not terribly well.
Mr Goldberg is already in the Engineering dept in the GPS-controlled transmission section.
Other than the process of mapping the road surfaces, it isn’t a major step in complexity. BMW already has both GPS linked transmission mapping and an analog version of MagneRide. BMW’s GPS transmission mapping uses topo maps.
Whether THOSE technologies are worth the complexity is another question.
Presumably, the GPS suspension cars wouldn’t need additional road sensors. The MagneRide car’s own suspension data, stamped with GPS location information, should be all the input that the master system needs to know about road conditions.
Still not good enough… at least in Michigan! Our road crews seem to be no more than a hi-vis vest army that randomly drops orange barrels and cold patch. Never at the same location. The database would never be able to keep up.
If the vehicle fleet were returning suspension data to the cloud, the cloud would know as soon as the first car passes over a new hole or a new patch. If you drive over a new change today on your way to work, the system certainly would be updated when you drive to work tomorrow.
And certainly your car’s own system could store the history of the roads you travel, even if the vehicle fleet doesn’t report back to Munich.
This is what Google has considered a possible learning and mapping exercise for their self-driving cars.
Would you have to pay for updates to the maps to account for repaving and potholes?
You’d just need data service; the cost of the server would be born by the manufacturer, as it’s part of their new vehicles anyway. All vehicles with GPS Super Ride are in two way communication with the server. Vehicles continually receive the current system settings for the location and lane of traffic, which configures the suspension. The vehicle’s suspension data is gps stamped and uploaded to the server as a report on current road surface. If the server decides that the road surface has changed, based on reported suspension data, it updates the system settings for that location and starts transmitting the new settings to vehicles that arrive at that location.
That seems similar to what some Mercedes-Benzes do with their “magic” body control (stupid name is stupid). I’m not 100% certain it uses SONAR but it’s got a few sensors of some sort that scan the road.
Uses a “multi-function camera”. Therefore Magic Ride Control doesn’t work in the dark. Or when it’s foggy. Or raining really heavily.
E.g. probably most of the time in England.
Norman Hossack’s Duolever suspension as used on BMW motorcycles.
http://i1175.photobucket.com/albums/r628/sparkie172420/Mobile%20Uploads/2014-10/DUOLEVER_zpsyo3uelx7.jpg
Yamaha GTS 1000 forkless suspension
http://silodrome.com/yamaha-gts-1000/
Thanks for that link! Interesting article on a subject I hadn’t known about! Two Wheel Tsunday for me!
http://m.memegen.com/zm8q07.jpg
Chrysler’s Torsion Bar setup. Very compact and solid. Gave a nice solid ride and pretty good handling. Not as softly sprung as coils
Jaguar IRS, with the rear half-shafts doing double-duty as the upper suspension link and using U-joints rather than CV joints; inboard brakes optional. Modern Jags use a more “pedestrian” multilink setup.
https://upload.wikimedia.org/wikipedia/commons/thumb/8/87/Jaguar_IRS_coloured_diagram.png/1280px-Jaguar_IRS_coloured_diagram.png
Also Lotus Elan, exc with squashy rubber thingies instead of ujoints or cvs.
Rubber guibos or no, I think this setup is called the Chapman strut, which is different from the Jag setup above. I don’t think thru axles actually act as a suspension link in this arrangement.
“What do you mean it will cost $1500 for a rear brake job on my XJS?!”
A multilink setup has many, many advantages over this. One of them being that you don’t need four shocks.
Sounds much more advanced than, but looks rather similar to the 1964 Corvair’s “we weren’t quite happy with swing arms + coil springs, so we added a hinged transverse leaf spring”
https://www.corvaircorsa.com/tech/earlyaxle.jpg
With all of the discussion of Citröen suspension, I’m really surprised that the system used on the 2CV hasn’t gained a mention yet.
Leading arms at the front, trailing arms at the rear. Connected laterally by what are essentially torsion bars, with interconnection front-to-rear via the pots – cylinders filled with oil and a pair of springs with a pseudo-counterweight between them. Front wheel goes up, the rear wheel is pushed down and vice-versa. In a sense, it’s the mechanical (as opposed to hydraulic) version of the DS hydropneumatic setup minus the high-pressure circuits, but is probably closer to BL’s Hydragas system in operation.
Dead simple and *very* effective. And much like a DS, good for lots of body roll but with excellent roadholding.
Brilliant in its (relative) simplicity, and far ahead of anything else in its time.