The WMSC have rejigged the F1 rulebook for ‘07 - twice as many tires available; no more Friday third cars, though the two-race engine change rule does not apply to Friday/Saturday practice running; new safety car regulations mirroring those used in Champ Car/IRL; new GPS-based flag marshal system including in-car warning light system, a system that was trialled a few years back but never completely implemented; and numerous tweaks to the ‘08 regs.