W116.org

Id be interested to know if anyone has a link explaining how these boxes of magic actually work.

Ive driven a vehicle equipped with a "constantly variable transmission" while here in Adelaide and its got me stuffed as to how it works.

its an infinitely variable gearbox that via computer control constantly changes its ratio so that basically, you can take off and the engine revs stay anywhere from 1500 to 2000 rpms from 0 to 100kmh, the only thing that changes is the vehicle speed. It's really very strange, there is no revving of the engine like a traditional auto or manual. Your position on the accelerator pedal determines the revs at which the transmission will keep the engine at while gaining vehicle momentum. The car also doesn't creep forward at traffic lights without the brakes on and is very responsive and takes off like it should. Bloody amazing.

dont they just drive great? this isnt exactly how they work but close,

"Continuously variable transmissions operate on the theory of pulleys; a large pulley connected to a smaller pulley with a belt or chain will operate in the same manner as a large gear meshing with a smaller gear. Typical CVTs have two opposing, cone shaped drums in them (one on the input, one on the output side) which can be moved in and out, controlled by the engine vacuum in the inlet manifold and engine RPM and centrifugal force acting on weights inside the conical drums. Moving the cones in and out has the effect of changing the driving and driven pulleys' diameter, thus changing the gear ratio. As there are no predefined steps in the system, it's referred to as continuously variable.
"

Dutch company DAF made cute little Euro-boxes back in the 60s and 70s with such a system.
Google DAF 44 or DAF Variant and see if there are any technical sites expalining.
Chris

Have a look at wikipedia Continuously_variable_transmission.

koan