Zacchia got his first taste of endurance racing at the 2003 24 Hours of Le Mans. He raced for Larbre Compétition in the GTS class using a Chrysler Viper GTS-R. His team mates were Patrice Goueslard and 1993 24 Hours of Le Mans winner Christophe Bouchut. They finished 16th overall and fourth in class. Larbre signed Zacchia prior to the 2004 Le Mans Series season. He reunited with 2003 Le Mans team mate Bouchut, his other team mate was ex-F1 driver Pedro Lamy. The trio won every race in the GTS class with their Ferrari 550-GTS Maranello, thus winning the championship. Zacchia focused on FIA GT for the next two seasons before returning to LMS in 2007, once again with Larbe with support from Aston Martin Racing as Larbre ran their DBR9. His team mate for the majority of the season was Gregor Fisken. For the final round, the 2007 Mil Milhas Brasil, the duo were joined by Roland Bervillé and Brazilian racer Fernando Rees. It was the final round at Interlagos that he won in the GT1 class but only half points were awarded due to less than five cars competing in that particular class. Zacchia and Fisken finished eighth in the GT1 standings, with their No. 51 car finishing sixth in the teams championship. In 2008, he was signed by Swiss team Speedy Racing Team Sebah for the Le Mans Series season. Zacchia raced a Lola B08/80-Judd in the LMP2 class along with team mates Andrea Belicchi and Xavier Pompidou The trio picked up points in only the first event of the season, the 1000 km of Catalunya where they finished second in class Zacchia and co. finished tenth in the drivers championship and seventh in the teams. Zacchia returned to the 24 Hours of Le Mans in 2008 for Speedy, teaming up with LMS team mates Belicchi and Pompidou. Their LMP2-spec Lola-Judd retired after 194 laps. 2009 was a quiet year for Zacchia, racing only on a couple of occasions in the International GT Open but also raced one round of the 2009 Le Mans Series season, reuniting with Larbre Compétition in the 1000 km of Catalunya. Only four cars competed in the GT1 class in which Zacchia raced in with a Saleen S7-R. Zacchia along with Roland Bervillé and Sébastien Dumez finished third in class and 22nd overall. 2010 saw another year of Le Mans Series racing for Zacchia, this time for Swiss team Hope Polevision Racing. He competed a full season in the one-make Formula Le Mans class along with Luca Moro and Wolfgang Kaufmann. The trio took their only class victory of the season at the 100 km of Spa. Zacchia and Moro finished runners-up in the drivers and teams championships. Zacchia is set to race in 2011 once again for Hope Racing in the Intercontinental Le Mans Cup driving an Oreca 01Hybrid chassis. It will be powered by a two-litre four cylinderpetrol engine from Volkswagen modified by Lehmann Motoren, badged as Swiss HyTech. It also features KERS, an automotive system whereby the kinetic energy of a moving vehicle is recovered under braking and stored in the flywheel for later use under acceleration, developed by Flybrid. Zacchia is set to compete with this car in the LMP1 class in the ILMC and at this year's 24 Hours of Le Mans alongside French driver Nicolas Marroc and Le Mans veteran and 1988 winner Jan Lammers.