Townley nudged Bobby Gerhart out of the way with seven laps left and held off Kyle Larson down the stretch Saturday on the 2 1/2-mile superspeedway.
Gerhart had the dominant car and seemed on his way toward winning his ninth ARCA Daytona race. But when Gerhart slowed down on the track, Townley tapped him and took off for the win. Gerhart pulled off the track, tried to return, but appeared to run out of gas. He finished 29th, five laps down.
Darrell Wallace Jr., set to become the fourth black driver to run a full-time schedule in a NASCAR series, was caught up in the only major wreck and finished 35th.
Larson was one of 20 first-time Daytona drivers in the traditional first race of Speedweeks.