The 1966 season saw the introduction of new, larger 3-litre engines to Formula One. Surtees's debut with Ferrari's new F1 car was at the 1966 BRDC International Trophy at Silverstone, where he qualified and finished a close second behind Jack Brabham's 3-litre Brabham BT19. A few weeks later, Surtees led the Monaco Grand Prix, pulling away from Jackie Stewart's 2-litre BRM on the straights, before the engine failed. A fortnight later Surtees survived the first lap rainstorm which eliminated half the field and won the Belgian Grand Prix.