user: Question: What start has a Ford Cosworth DFX as the engine, a year later than 1981, and Kraco Enterprises as the entrant?
Columns: ['Year', 'Chassis', 'Engine', 'Start', 'Finish', 'Entrant']
Types: ['real', 'text', 'text', 'real', 'real', 'text']
Sample row: [1981.0, 'Phoenix 80', 'Ford Cosworth DFX', 12.0, 4.0, "Jerry O'Connell Racing"]
SQL:

assistant: SELECT "Start" FROM "Table" WHERE "Engine" = 'Ford Cosworth DFX' AND "Year" > 1981.0 AND "Entrant" = 'Kraco Enterprises';