Longin started his racing career in the Belgian Racing Drivers Club. In 2013 he was fielded by Hoppa Racing in a Renault Clio. The following year, in a BMW M3, Longin won the championship in Division 3. In 2014 Longin made his debut in the NASCAR Whelen Euro Series as a part of the PK Carsport formation. At Tours Speedway Longin finished second, behind Denis Dupont, in the second Elite 2 race. At the Nürburgring the Belgian driver scored another two top-ten finishes. Longin's first appearance at the 24 Hours of Zolder came in 2014. The Belgian driver made his debut for the Australian MARC Cars formation with teammates Kris Van Kelst, Ryan McLeod, Hadrian Morall, and Mich Benton. The team finished twelfth overall, second in class.
