[andrensairr]

I know it's OT but I wanna know what your old Citroën was. My first car was an S1 BX. Plasticky 80s goodness. I know it's not everybody's idea of a classic (at least in Australia where Citroëns aren't particularly common) but I loved it.

[ErroneousBosh]

At the time I had a 1989 XM 2.0, but at various times I've had a couple of CXes, several XMs, a couple of GSAs, a BX briefly, and an AX GT.

One of the XMs was the 3-litre 24-valve one which would sit comfortably at twice the legal limit, with the only real difference being the stereo had to be a couple of notches louder and the trees and road signs came up twice as fast. Oh, and the trip computer showed an astounding 8MPG - you wouldn't be doing 147mph for long because you've got less than an hour of fuel in the tank at that speed.

The AX GT was the carby one, basically their 950cc hatchback with the 1.4 out of a BX dropped in and a lumpy cam and twin-choke 2x32mm Weber carb. It was a little pocket-size tin of hooliganism.

The CXes were probably the most refined of the lot. Look up DIRAVI steering - fully powered, no mechanical connection between the steering wheel and road wheels when it's working normally.

[foobarian]

Our uncle had a CX when we were kids. When he would visit we loved waiting in the driveway for him to start it so we can watch the air suspension engage and lift the car a good foot up.

[ErroneousBosh]

Hydropneumatic suspension :-) There's a hydraulic pump about the size of a coffee cup driven off the end of the camshaft, which provides power to the suspension, braking system, and steering.

The suspension has no springs or shock absorbers - there's a "sphere" screwed into the end of each suspension cylinder with a bubble of nitrogen trapped by a rubber sheet that acts as a spring, and a set of spring-loaded valves kind of like the ones in a shock absorber piston to set the damping rate.

For the brakes, the hydraulic pump fed the ABS block through a shuttle valve under the pedal. When you press the pedal it does not move! Or, hardly at all. I takes a little getting used to and the brakes feel really harsh until you realise you don't need to welly it down hard - just gently touch it. The back brakes use pressure from the rear suspension, so they're more effective the heavier the car is.

The steering is amazing. When the engine is running the road wheels and steering wheel are not really connected. There's a linkage through a shuttle valve and when you turn the steering wheel it acts as a servo, with the wheels being moved entirely by hydraulic pressure. The Danfoss valves in normal power steering systems work a bit like this but they use a bendy spring, and the hydraulics only "help".

To make it respond properly at speed there was a heart-shaped cam in the steering box, with a sprung piston pushed into it by hydraulic pressure from a speed governor on the gearbox. The faster you go, the more pressure on the piston, and the harder the spring presses a roller into the cam. At idle with the car stationary you can move the steering wheel and it'll spring back to the middle by itself, and at 70mph you can barely move the steering wheel at all.

It's really sensitive and the first time you drive one you find yourself zig-zagging down the road until you get used to just leaving your fingertips on the rim of the wheel and basically just touching the side you want it to turn to.

They're not terribly fast but you can gobble up the miles surprisingly quickly, and I've never driven anything where you arrived so relaxed.

[foobarian]

That is amazing, thank you for this note!

[rkomorn]

Not OP but my dad drove a CX for a while, but the real treat was our friend's DS.