Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_52993 ( "Constructor" text, "Chassis" text, "Engine" text, "Tyres" text, "Driver" text, "Rounds" text )

### Question ###
What engine was used during the race driven by Jan Lammers using a chassis of d3 d4, making a tyre of g and rounds of 4-6?

### Accurate SQL ###

SELECT "Engine" FROM table_52993 WHERE "Tyres" = 'g' AND "Chassis" = 'd3 d4' AND "Driver" = 'jan lammers' AND "Rounds" = '4-6'