The Race::2008 Montmagny 100 was a Serie ACT-Castrol event held at Track::Autodrome Montmagny on August 23, 2008. American transplant Mario Gosselin rolled to his first series victory, leading the last 28 laps of the race but only managing to hold off Donald Theetge by one carlength at race's end. Alexandre Gringas finished 6th to hold a seven-point championship lead on Karl Allard (10th).