Kammala jumla mai zuwa: Bayan gabatarwar ta a cikin 1966, ƙungiyar tsere ta 275 GTB / C ta yi tsere da ƙungiyoyin tsere masu zaman kansu da digiri daban-daban na tallafin masana'antar Ferrari, gami da NART, Maranello Concessionaires, Scuderia Filipinetti, da Ecurie Francorchamps. An shigar da uku 275 GTB / Cs a cikin
1966 24 Hours na Le Mans, biyu daga cikinsu sun gama. Maranello Concessionaires-ya shiga 275 GTB / C (shasi 09035) wanda Roy Pike da Piers Courage suka yi ya gama na 8 gaba ɗaya kuma na 1 a aji, yayin da Ecurie Francorchamps 275 GTB / C (shasi 09027) wanda Claude Dubois da Pierre Noblet suka yi ya gama na 10 gaba ɗaya kuma na 2 a aji. Sauran nasarori masu ban mamaki sun haɗa da 1st a aji a 1967 Targa Florio, wanda Tullio Sergio Marchesi ya tuka. Marchesi ya ci gaba da lashe gasar zakarun Italiya ta GT a shekarar 1966 da 1967 yana tuka 275 GTB / C chassis 09007.