CREATE TABLE table_55533 ("Driver" TEXT, "Constructor" TEXT, "Laps" FLOAT, "Time/Retired" TEXT, "Grid" FLOAT)

What is the largest grid with a Driver of ralph firman, and a Lap smaller than 18?
SELECT MAX("Grid") FROM table_55533 WHERE "Driver" = 'ralph firman' AND "Laps" < '18'
SELECT MAX("Grid") FROM "table_55533" WHERE "Driver" = 'ralph firman' AND "Laps" < '18'