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_name_71 (engine_s_ VARCHAR, chassis VARCHAR, year VARCHAR)

### Question ###
What is the engine(s) on the car before 1978 with ensign n177 chassis?

### Accurate SQL ###

SELECT engine_s_ FROM table_name_71 WHERE chassis = "ensign n177" AND year < 1978