Organisers outlined a series of rule changes for the 2015 season in October 2014: • The amount of success ballast is now implemented to the top ten drivers on the grid and the championship heading into a weekend instead of five. With more drivers now carrying ballast, the weight has been increased with the maximum being heavier than in previous years. The maximum success ballast is for the championship leader, down to for tenth place. Rear-wheel drive (RWD) cars carry their success ballast as far forward in the cabin as possible, in order to better equalise the front to rear weight balance between both drivetrain formats. •
Cosworth and
Xtrac independently analyse the start-line performances and in-gear acceleration of front and rear-wheel drive cars with a view to more equalising them through engine management programming. • All engines have now been re-tested and re-validated by both
TOCA and an independent specialist company – resulting in a boost level being set for each car and engine type for the season. As the larger amount of success ballast has a greater effect than before, the lap-time boost level adjustment can be dropped. • Each car must still use the
Dunlop soft tyre for one race at nine events – the
Thruxton event does not apply as the soft tyre is not used at the venue – but each car must use them three times in race 1, three times in race 2 and three times in race 3 during the course of the season. • The grid for race 2 at each event is set in the order of the fastest lap times achieved in race 1. If during race 1 a driver changes one or more tyres of the same type then any quicker lap time (if achieved) after that tyre change is discounted. • The Jack Sears Trophy will be awarded to the top 'Rookie Driver' of the year. ==Race calendar==