 The Opel Monza Concept is a four @-@ seat coupe plug @-@ in hybrid concept car with gullwing door unveiled at the 2013 Frankfurt Motor Show . The concept shares the same basic plug @-@ in hybrid setup as the Chevrolet Volt and Opel Ampera , but using a turbocharged 1 L 3 @-@ cylinder natural gas @-@ powered engine as its range extender instead of General Motors ’ current 1 @.@ 4 L gasoline engine . According to Opel , this concept is the role @-@ model for the next generation of Opel cars , and because of its modular chassis design , future cars based on it would be able to accommodate gasoline , diesel or electric power . 
