Drivers Jean-Karl Vernay and Alejandro Garcia completed two days of testing aboard the revived Isotta marque's Tipo 6 Competizione LMH at Estoril.
French outfit Duqueine will enter a single car in the 2024 WEC under the Isotta Fraschini Duqueine Team banner after the manufacturer's split with originally confirmed partner Vector Sport was announced last month.
Isotta motorsport boss Claudio Berro has acknowledged that the change of team had been made for financial reasons, with the LMP2 class regulars stepping up from the European Le Mans Series for a maiden WEC campaign.
Berro said: "I am very satisfied with the first test done by the Isotta Fraschini Duqueine team. It was also Alex Garcia's first time driving a hypercar and he behaved very professionally, assisted by Jean -Karl Vernay.
"The two Portuguese days saw several long runs in which the car performed perfectly, which allowed us to collect a lot of information on the tyres and on the set-up and aerodynamic settings."
Vernay, a Le Mans 24 Hours class winner in 2013 who most recently raced for Hyundai in the FIA ETCR - eTouring Car World Cup, and reigning ELMS LMP3 champion Garcia are the first two drivers confirmed to race the Isotta, which has been built by long-time Ferrari technical partner Michelotto and features a front-axle hybrid system.
Source: Autosport