GTA announced requirements (Balance of Performance (BoP), etc.,) for each car to be applied for the OKAYAMA GT 300km RACE, Round 1 of the 2026 AUTOBACS SUPER GT series. These requirements will be announced in a bulletin before each round of the series.
Please note that the contents from the bulletin below are excerpts selected for ease of understanding and they should not be taken as the actual contents in the officially released bulletin. In case of a need for a precise interpretation, be sure to check the original bulletin.
（Blue underlines: Changes from the 2026 Official Test at Fuji）
■GT500 Class
A fuel flow restrictor with a capacity of 90.2 kg/h must be fitted. The refueling flow restrictor must maintain the shape of the “Flow Restrictor” shown in Figure 3-2, Article 10.3.2, Chapter 10, Part 3 of the 2026 JAF National Technical Regulation, and the minimum internal diameter of the narrowest section shall be Φ25 mm.
■GT300 Class
For FIA GT3 cars in the GT300 class, the BoP (Balance of Performance) is determined through cooperation between GTA and SRO (the organizer of series such as the IGTC and GTWC). Based on this framework, the technical requirements for GT300 cars are defined. With a wide variety of car models competing in the GT300 class, fans are encouraged to pay close attention to the BoP as well.
○GT300
*1 The refueling restrictor must maintain the shape of the “flow restrictor” in accordance with the 2026 JAF National Technical Regulation Chapter 3, Art. 10 10.3.2, figure 3-2, except for the minimum internal diameter.
*2 For HYBRID cars, data separately specified by the GTA must be submitted.
○GT300 Mother Chassis
*1 The refueling restrictor must maintain the shape of the “flow restrictor” in accordance with the 2026 JAF National Technical Regulation Chapter 3, Art. 10 10.3.2, figure 3-2, except for the minimum internal diameter. *2 Minimum ground clearance: a 10 mm spacer shall be fitted between the reference plane and the skid block with a thickness of 10 mm (±2 mm). *3 The fuel capacity carried on-board is limited to 110 liters.
○FIA-GT3
All cars * The shape of the refueling restrictor must maintain the shape of the “flow restrictor” in accordance with the 2026 JAF National Competition Vehicle Technical Regulations Chapter 3, Art. 10 10.3.2, figure 3-2. * Any additional ballast must be mounted in accordance with the 2026 International Sporting Code, Appendix J, Article 257A, Article 204. *Covering the entire surface of aerodynamic devices with tape or paint is not permitted.
Vehicles indicated in the Notes column *1 An air restrictor with a shape conforming to the dimensions specified by the FIA must be fitted. *2 The above table shows the required specifications when using the Krontec 88K SL. When using other Krontec rigs parts, the specification should be 27.4mm. *3 Only SRO‑approved springs specified by GTA may be used. (For other vehicles, only FIA‑homologated springs may be used.)
○Maximum boost pressure
The maximum boost pressure level is calculated by applying the above boost pressure ratio to the standard air pressure announced by GTA. At each race event, the teams must adjust the maximum boost pressure in accordance with the local air pressure announced by GTA.
