In the summer of 1959, work commenced with Julius Lindblom in Sweden transforming a Citroën DS19 into an advanced prototype vehicle that automatically inclined the car body up to 9 degrees when driving in a curve.
Julius Lindblom patented his suspension innovation but it was never commercialized for cars. This tilting technology is used today in high-speed passenger trains, reacting to curves and inclining their bodies.
The DS19 story is fascinating and now well documented by the car’s present owner Mikael Thelin who is doing an extensive restoration. Read about the DS19’s history, surprises and challenges in returning what he refers to as the Hjulius 1958 Citroën DS19 to its original showroom condition here: http://www.hjulius.com/Hjulius/History.html.
Video of the DS when it was equipped by Julius Lindblom to tilt can be viewed here:
Early on in the development of the DS, Paul Magès, the Citroën engineer who led his team in the invention of hydropneumatic system, pushed the suspension to counteract the centrifugal force when cornering. The system, called “antigite” (based on a physical principle) was fitted on six DS test cars in 1955 but wasn’t fitted on production cars. (More on why not can be found here: https://www.citroenet.org.uk/miscellaneous/hydraulics/hydraulics-2.html.)
40 years later, Citroën chose to use the same principle (but electronically based) on the Xantia Activa.
A fellow in the U.K who may have been a professor at the Open University , had transformed his late model DS Safari with an Activa suspension as well as he had transformed his 2347cc engine with dual webbers twin choke if my memory serves me correctly, he had used a DS23 EFI head and instead of transforming it with a fuel injection, he had it custom made pipe work using the carburetors instead. He had written in his advertisement , all that he had done to achieve tons of power and how the Hydractive suspension with the computer controlled independent valves were fitted onto each of the corners to activate the side , I.e front to rear wheels to firm up the side where upon cornering, that side would fir up, not harder, just firmer, so that it have no lean towards the steered side.
It had come for sale several years ago, I don’t know who owns it now, but you may be able to do a search and find it on the G👀gle