The second generation Quattroporte, the Tipo AM123, arrived in 1974 and was a Citroen era car and as such was based on an extended Citroen SM chassis.
It was in effect a re-skinned SM, using the 3-litre V6 engine that Maserati had supplied Citroen for that model. It was also front-drive with Citroen’s hydro-pneumatic suspension and the moving headlights that were first seen on the gorgeous Citroen DS.
Marcella Gandini designed the car with Bertone constructing them. However, it was due to be released just as the infamous 1973 Oil Crisis happened - thanks to decisions made by the US Government from the late 1960s. It all boiled over in 1973/74 and killed off several marques with their low volume cars. Subsequently neither Maserati nor Citroen could get the revised European type approval so the limited volume built ended up being sold in the Middle East or Spain - who ignored the EEC directives!
The V6 installed only had about 200hp and was deemed gutless for a large, heavy vehicle, so Citroen asked Maserati to develop a new V8 motor to try and resuscitate the model. Unfortunately Citroen collapsed part way through the development of the new engine and only twelve cars were ever built between 1976 and 1978 after the prototype appeared in 1974!
So if you see a Quattroporte II in the wild, it is a rare beast!