Disney Pixar’s “Cars 2″ is off to a racing start at the domestic box office, cuming $8.3 million at 4,115 locations as of Friday afternoon.Sony’s “Bad Teacher” grossed $1.4 million in 3,049 domestic plexes, with B.O. observers expecting an uptick with the over-25 Friday night auds. “Teacher” tracking, which popped Friday, puts the film in line to collect in the high $20 to low $30 million range through Sunday, according to insiders. Even if the laffer doesn’t hit that range, a bow north of $20 million would still be an exceptional start given the film’s production costs at just under $20 million. “Cars 2″ will likely top out around $60 million for the weekend. The toon’s Friday numbers suggest that more families headed to the multiplexes in the afternoon than anticipated, perhaps due to many schools’ summer vacations. Pic should still show a sizeable uptick on Saturday with parents not working. “Cars” will likely see the frame’s best hold on Sunday as family films typically play better than any other genre. “Teacher” should see a nice Friday evening cume with the popularity of R-rated comedies like “Hangover 2″ and “Bridesmaids” likely boosting appeal for the Sony laffer. “Bridesmaids” saw a 26% uptick on opening Saturday numbers over Friday numbers with a 26% downturn on Sunday. B.O. observers could expect to see similar percentage shifts for “Teacher.” “Cars 2″ is in the lead with Friday ticket sales, accounting for 72% via online ticketing service Fandango.