Table schema:
CREATE TABLE table_19524523_1 (champ_car_world_series__2004_2007_ INTEGER, usac__1956_1995_ VARCHAR)

Question: What is the most Champ Car wins for any driver with a USAC record of 2?
SQL: SELECT MAX(champ_car_world_series__2004_2007_) FROM table_19524523_1 WHERE usac__1956_1995_ = 2