user: Question: What was the highest grid value for riders with manufacturer of Aprilia and time of +1.660?
Columns: ['Rider', 'Manufacturer', 'Laps', 'Time/Retired', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Sergio Gadea', 'Aprilia', 18.0, '38:09.44', 8.0]
SQL:

assistant: SELECT MAX("Grid") FROM "Table" WHERE "Manufacturer" = 'Aprilia' AND "Time/Retired" = '+1.660';