Combine 1/4 cup oil, the vinegar, garlic, salt, and 1/4 tsp. pepper in a bowl. Set aside.
Heat grill to high (450° to 550°). In a large bowl, combine remaining tbsp. oil with remaining 1/4 tsp. pepper. Turn salmon in oil to coat.
Set out rows of 3 salmon chunks on a work surface. Unroll pancetta slices into strips and wrap strips once or twice around salmon, weaving long pieces between chunks. Skewer each row of salmon with chunks slightly separated.
Oil cooking grate, using tongs and a wad of oiled paper towels. Set kebabs on grate, then grill, covered, turning once, until fish is barely cooked through, 4 minutes.
Arrange kebabs on plates. Stir parsley into dressing; spoon on top of kebabs. Serve with warm, crusty bread for dunking.
Note: Nutritional analysis is per serving.