Pontiac Banshee XP-798 - http://www.carstyling.ru/
The Pontiac Banshee XP-798 was a concept car built in 1966.
The Banshee XP-798 was John Z. DeLorean’s concept of a "Mustang Fighter" with all wheel independent suspension, a 421 V8, and fold down rear seats. Of note were the doors; flip-up panels on the roof augmented the passenger doors.
The Banshee was never shown to the public: GM President Cole thought it would eat into the Corvette’s market share and Chevrolet was developing the F Car which became the Camaro/Firebird. One could guess that the doors of the Banshee made their way into the design parameters of the DMC-12 in 1975, but there was no mention of this.
Note that in 1988 the Banshee name was revived by Pontiac into a Show Car to demonstrate a Firebird for the 90’s.