In 1970, production of the Quattroporte I (Tipo AM 107) stopped.
The following year Pietro Frua produced a Quattroporte Frua based on an Indy 4900 (Tipo AM 121).
The magnificent QPII Frua V8 will never be mass-produced because Citroën blocks this project after only two examples have been built (one for the AGA Khan and the other for King Juan Carlos) and imposes its Quattroporte project with a front V6 engine (the one of the SM), on an SM Opera chassis (4 doors) and fitted with Citroën technologies based on a design by Gandini for Bertone.