In 1970, the Grifo Series II was introduced, with sleeker styling and hide-away headlights and powered by big-block Chevrolet 454 V8 (7.4-litre) engines. It was replaced in 1972 with the Grifo IR-8, which used a small-block Ford Boss 351 engine (5.8-litre) as its power-train. This was the last new Iso of any type, as the manufacturer went bankrupt; it shut down and ceased all operations permanently in 1974. The bankruptcy had a number of causes, perhaps the largest being the 1973 oil crisis, which significantly reduced demand for cars with large displacement engines.