Place the cake mix, *1 cup (1 1/3 cup) undrained crushed pineapple, sugar, oil, and eggs in a large mixing bowl. Blend with an electric mixer on low speed for 1 minute. Stop the machine and scrape down the sides of the bowl with a rubber spatula. Increase the mixer speed to medium and beat for 2 minutes more, scraping down the sides as needed. The pineapple should be well blended into the batter. Pour the batter into the prepared pan, smoothing the top with the rubber spatula. Place in the oven.