The Japanese Formula 4 is an open chassis class, open for all chassis manufacturers. Since 2012 the engines have a maximum capacity of 2,000cc. Currently the cars are allowed to be fitted with a Honda K20A, Toyota 3ZR or Nissan SR20 engine. Since 2010 the cars use a monocoque chassis in stead of a tube frame. In the first year of the monocoque chassis most cars were West Racing Cars. Later came more cars built by Tokyo R&D, Mooncraft and ZAP. Starting in 2015 the Japanese Formula 4 will adapt the regulations of the FIA Formula 4.
- ↑ "JMIAが主体となりFIA-F4車両の開発を開始し、 2015年よりマーケットへの投入を目指します。". Japan Motor-Racing Industry Association. http://www.jmia.jp/news/ns131128.html. Retrieved 2 January 2014.