When viewed in slow motion, during the scene where the Road Runner whizzes through the cement and it splashes onto Wile E. Coyote, the cement begins to part and splash *a second before* the Road Runner slices through it.
When the Coyote fails to stop the Roadrunner by posing as a blonde hitchhiking female and the Roadrunner comes back wearing the blonde wig and holding a sign, the Roadrunner does his usual tongue-flickering sound before he speeds off, but no tongue is seen.