On August 26, 1945, the State Defense Committee published Order № 9905, which prescribed the start of production of the 4-door Kadett on the Moscow small car plant "without any changes to the design". But implementation of the plan was far from smooth. The Rüsselsheim plant had been deeply involved in the Nazi war effort, producing aircraft engines for the Luftwaffe, and consequently has been heavily damaged by the Allied air raids. Very little was left to be salvaged – mostly incoherent drawings and plans, with several stamping dies for the 2-door version of the Kadett to add.
The GSi's engine mapping had been carried out by Opel tuning specialists Irmscher. A model with the 82 PS (60 kW) 1.4 L multi point fuel injected engine, which was otherwise mechanically identical to the GSi, also became available as the Nova SRi in the United Kingdom. In January 1988, a turbocharged version of the Isuzu diesel engine was introduced, with power increased to 67 PS (49 kW).