V8 Supercars will radically revamp some of its event formats next year in what it's billing as "the most significant changes in the history of the sport."
Six of next year's 15 events will run to a "60/60 Super Sprint format" on Saturdays, with a 120km race split into a pair of 60km halves and separated by a 15-minute break.
A qualifying session will determine the starting order for the first half, while the running order after 60km will set the grid for the second half, which will begin with a rolling start.
The official finishing order will be the positions at the end of the second 60km, while neither half will feature refueling. Sunday's races, which will both be individual 120km contests, will also be devoid of pit stops.
The six venues that will stage events running to the new format are Symmons Plains, Barbagallo, Hidden Valley, Queensland Raceway, Winton and Phillip Island.
The V8 Supercar Commission also announced that tire compounds will be changed for each event in order to provide the "most exciting race" at each venue.
Only three rounds, those at Adelaide, Townsville and Homebush, will retain their 2012 race format and tire compounds. Along with the two-driver Sandown, Bathurst and Surfers Paradise enduros, they will be the only events at which refuelling is allowed.
V8 Supercars COO Shane Howard said the changes were aimed at improving the racing and capitalizing on the impact of Nissan and Mercedes joining the championship next year.
"These are the most significant changes we have made to our formats in the history of the sport," he said. "With the new marques joining Ford and Holden in 2013, it was an opportunity for a change across the board while continuing the great traditions of our signature events. These changes are purely designed for the teams and drivers to race hard and have a real go."
The final formats of Pukekohe, Yas Marina and Circuit of The Americas events – the latter being the Australia-based series' U.S. debut – will be finalized at a later date.