1. Ford Windsor small-block engines (302, 351W, etc.): 1-5-4-2-6-3-7-8
2. Ford Modular engines (4.6L, 5.4L, etc.): 1-3-7-2-6-5-4-8
3. Ford Coyote engines (5.0L): 1-5-4-8-6-3-7-2
4. Ford Duratec engines (2.3L, 2.5L, etc.): 1-3-4-2
5. Ford EcoBoost engines (2.0L, 2.3L, etc.): 1-5-3-6-2-4
It's always best to refer to the specific vehicle's owner's manual or repair manual for the exact firing order for your particular engine.