Both engines were later versions of Fiat's twin-cam design and inherited from the Lancia Delta Integrale, winner of the World Rally Championship a record six times.
Obidva motory boli novšie verzie Fiat Twin-CAM dizajnu a zdedené z vozidla Lancia Delta Integrale, ktorý bol 6-krát víťaz na Majstrovstvách sveta v rely.