user: Question: What was the Engine, when the Chassis was Bugatti T51, and when the Entrant was a Private entry?
Columns: ['Driver', 'Entrant', 'Constructor', 'Chassis', 'Engine']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Ernst-Günther Burggaller', 'German Bugatti Team', 'Bugatti', 'Bugatti T35B', '2.3 L8']
SQL:

assistant: SELECT "Engine" FROM "Table" WHERE "Chassis" = 'Bugatti T51' AND "Entrant" = 'Private entry';