Police Quest Driving help

Joey in pq, when you drive, you can hit like F8 to go faster and stuff. what command would i use to do this, withOUT making everything else go faster. so like only my guy moves fast if i press it, and not everyone else (do i doubt it is the interpreter cycles variable.) please let me know what code to use. i already defined F4 as c34. just dont know what code to put in logic.000
Joel try step.size