Hydropneumatic is a type of automotive suspension system, invented by Citroën, and fitted to Citroën cars, as well as being adapted by other car manufacturers, notably Rolls-Royce, Mercedes-Benz and Peugeot. It was also used on Berliet trucks. Similar systems are also used on some military vehicles. The purpose of this system is to provide a soft, comfortable, yet well-controlled ride quality. Its nitrogen springing medium is approximately six times more flexible than conventional steel, so self-leveling is incorporated to allow the vehicle to cope with the extraordinary suppleness provided. France was noted for poor road quality in the post-war years, so the only way to maintain relatively high speed in a vehicle was if it could easily absorb road irregularities. While the system has inherent advantages over steel springs, generally recognized in the auto industry, it also has an element of complexity, so automakers like Mercedes-Benz, British Leyland (Hydrolastic, Hydragas), and Lincoln have sought to create simpler variants. This system uses a belt or camshaft driven pump from the engine to pressurise a special hydraulic fluid, which then powers the brakes, suspension and power steering. It can also power any number of features such as the clutch, turning headlamps and even power windows. The suspension system usually features driver-variable ride height, to provide extra clearance in rough terrain. The suspension setup is referred to as 'oléopneumatique' in early literature, pointing to oil and air as its main components. There have been many improvements to this system over the years, including variable ride firmness (Hydractive) and active control of body roll (Citroën Activa). The latest incarnation features a simplified single pump-accumulator sphere combination. The system had one key negative impact on the inventor, Citroën - only specialist garages were qualified to work on the cars - making them seem radically different from ordinary cars with common mechanicals. Auto manufacturers are still trying to catch up with the combination of features offered by this 1955 suspension system, typically by adding layers of complexity to an ordinary steel spring mechanical system. To put it simply,yes,yes they are.Just because it wasn't here in the states doesn't mean it wasn't done
From Cadillac history archives: The ratings were 300/325 for 1957, when compression went to 10:1 and the line was again rebodied, emerging with blockier but still evolutionary styling inspired by the Orleans, Eldorado Brougham, and Park Avenue show cars of 1954-55. Reaching into the luxury stratosphere, Cadillac unveiled a production Eldorado Brougham priced at a princely $13,074. Like its Motorama namesake, it was a surprisingly compact, low-slung pillarless sedan with a special 126-inch-wheelbase chassis, center-opening doors, and a brushed stainless-steel roof (one of Harley Earl's favorite touches). Standard quad headlights were an industry first shared that year with Lincoln, Nash, and some Chrysler Corporation cars. The Brougham's most intriguing mechanical feature was its unique air suspension, the work of engineers Lester Milliken and Fred Cowin. Based on systems used for commercial vehicles since 1952, it employed an air "spring" at each wheel comprising a domed air chamber, rubber diaphragm, and pistons. Fed by a central air compressor, the domes were continually adjusted for load and road conditions via valves and solenoids for a smooth, level ride. Cadillac's system differed from "air ride" options at other GM divisions in being "open" (taking in air from outside) rather than "closed." Unhappily, cost and complexity were too high relative to benefits. The air domes leaked, and dealer replacements were frequent, leading many owners to junk the system in favor of conventional coil springs. Four years later, Cadillac and GM abandoned air suspension altogether. After two years and 704 units, the Brougham was fully restyled and its final assembly farmed out to Pininfarina in Italy. Only 99 were built for '59, another 101 of the near-identical '60s. Though clean-looking (lines actually previewed Cadillac's 1961 styling), these were larger (130-inch wheelbase) and heavier cars that weren't put together very well (bodies contained lots of lead filler). They're collector's items now, but restoring one is a chore. Just saying...
yeah it a 51 dodge coronet mordor....i am going to bag it ..for the front i plan on making the lowered a-arms..the rear is pretty simple ...should come by my after hours shop ..we'll shoot the bull and pound some brews
i dont like using 2 tanks ...one tank w/2 compressors is all you need in my opinion ...this system works great ,eric(owner) loves it, requires 120 psi to lift the front to full lock up.i also in stalled a check valve to the front valves to help it stay up even when tank is drained .
how many valves are there? doesnt seem like 8, also what brand.. also, i would agree taht 2 - 5 gallon tanks are needed for this car
there are four valves on it ...air ride pro, first time using them and i dont really like them ... 2 tanks is stress on your compressors...you would need 4 of them just to lengthen the life of your comps ..you want air pressure more than air quanity , thats why i always recommened engine driven air , and one tank ...there has been countless number of guys that come into the shop and we replumb there system to one tank , and there much happier with it
Hey Evilone,not offended,just tired of the "It's not traditional" or "It's not period correct" statement coming up involving air suspension.Seen it a million times,heard it at many car shows,and I always chime in with this info,which shuts down the nay sayers.Same thing when I hear that Radial tires aren't period correct or traditional.It all depends on what period you're talking about.In the 60's adjustable susp[ensions were all the rage with customizers and lowriders,end of story.Don't believe me?Look up the X-Sonic,and if they did that,you know someone was screwing around with the GM ride leveling systems.
i read an article like 3 years ago about air suspensions, and it dated back to the (if i can re-call right)30's and 40's ...was being used on race cars ..i'll do my best to try and find it
I tell you what Hooligan,I do not doubt that some one,some where,was using air bag suspension in the 50's and 60's.That being said,ask any and all the "Grey Beard's"that you know when the first time they remembered seeing a hot rod ,or a custom with air bags. Im sure many more folks in the time period above were using some sort of 4 link system on race cars,but still yet,they are not considered by most to be "traditional". I personally like the look of a car slammed on the ground,be it with air bags,or any other means.None the less,it still doesn't seem "traditional".Just like nitrous,4 link suspension,pastel paint jobs,or any of the other thousands of un-HAMB friendly stuff the "traditional police" like to gripe about.
How about the X-Sonic in 1960 with a Hydraulic setup to drop the car as low as possible and raise it to a safe driving height?Hmmm,and I've heard hydraulics get slammed on here too.Seems pretty period correct to me for a 60's car. http://www.kustomrama.com/index.php?title=X-Sonic
Oh,and most of the grey beards I know can't be bothered to remember that far back,and most of them are building glass bodied 32's.
But it's so true.Most of the gray beards I know are in Over The Hill Gang,well,at least my neighbor Jerry is,and I know one of his is for sure glass,one for sure is steel(I still want that damn car in a bad way),and not sure about the other.
I would like to see Ryan actually due some research and post regarding this subject matter.Seems he can come up with a lot of info even most of us with a lot of knowledge and great tech savvy can't find.I also know at least one of his rides has air ride suspension
never got around to posting these pics ..hope someone digs'em ... ash tray modified for the air bag switches . as requested by owner
i found the article ...its in the july 06 issue of lowrider magazine ..firestone bagged a buick and a cord in 1936
he finally brought back the car for a engine driven compressor .. in a 5 gallon tank 0 to 175 psi in a heart beat !!
went to a lowrider show this weekend ...and i seen this frame reinforcement on alot of cars ...and all were poorly executed ,wish i would have took pictures ...but i decided to do it to the caddy while i still had it to see what the big deal was ...
Dated June-July 1958,before the X-Sonic was even fitted for Hydraulics,and,with the information I posted,air suspension was being used during WWII in foreign vehicles,and according to another response on this thread by SouthernSteel,was being used on race cars in the 30's and 40's.Sounds traditional to me. Stole these from another thread that got deleted: Belowicture of the 30's vehicle in the lower corner,under it says "Air experiments in the mid-30's led to today's systems.Photo courtesy of National Rubber Bereau"
Souther Iron Like the work, especially the retrofit on the factory AC comp. Can you post a few pics of the rear set up fitted with the bag? Looks like you mounted the back fairly close to the pivot point since you didn't like the factory location. Thanks
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