Toyota heads into the finale with the advantage, as TOM'S pair Sho Tsuboi and Ritomo Miyata take a seven-point lead to Motegi over NDDP Nissan rivals Katsumasa Chiyo and Mitsunori Takaboshi.
ARTA Honda pair Nirei Fukuzumi and Hiroki Otsu are also still in the running, albeit facing a daunting 16-point deficit with 21 left on offer.