Heat olive oil in an 8-qt. pot over medium-high heat. Add bell pepper and cook, stirring, until slightly softened, about 3 minutes. Add chorizo and garlic; cook, stirring often, until chorizo is lightly browned, about 2 minutes.
Add wine, 1/2 cup water, and the clams; cover and cook until clams have opened, 6 to 8 minutes. Discard any unopened clams. Sprinkle with parsley and serve with bread.