Changing characters
Howard Payne is a truly evil villain, but the character wasn't always going to be the big bad of 'Speed'.
In earlier drafts of the script, it was going to be revealed that Jack Traven's partner Harry Temple (played by Jeff Daniels) was the real villain of the film who had strapped the bomb to the bus.
However, after Dennis Hooper came along and dazzled the studio with his villainous performance, the movie was re-written to make Howard the ultimate bad guy.