Super Taikyu is a Japanese touring car race; taikyu means “enduro” or endurance. Japanese Super GT racecars are total racecars only and so it’s hard to find stock parts. Super Taikyu cars are like tuned stock body cars. The regulations say the body must be stock. The engine must be stock but you can have approved pistons and connecting rods; you can also change head gasket but must use a catalytic converter. Intake manifold and header must be genuine parts. Super Taikyu racecars can have stripped interior; suspension and exhaust are race spec. So you can have some tuning parts and be OK. You can have lightweight doors on these cars: CZ4A Lancer Evolution X, FD2 Civic Type R and WRX STI; their doors are very heavy and not good for racing.
Super Taikyu has five classes (one new class is STX, which is for FIA GT race cars): Chevrolet Corvette, BMW Z4, Porsche GT3 and NISMO 380RS are in ST-1; Mitsubishi Lancer Evolution and Subaru Impreza are in ST2; BMW M3, Nissan 350 and 260Z, Honda NSX, Lexus IS350 and Mazda RX-7 (FD3S) are in ST3; Honda S2000, Honda Integra Type R (DC5) and Honda Civic Type R (FD2 and FN2) are in ST4; Honda Fit and Toyota Vitz (YARIS) are in ST5, but only two or three cars take part in ST5 class but we can see Honda Fit RS versus Toyota Vitz RS (YARIS). About twenty years ago, there was Group A race in Japan. We could see Honda Civic versus Toyota Corolla Levin (Trueno) and we got excited to see it and many car guys talked about Honda versus Toyota or FF versus FR. I know Fit and Vitz are FF. I think ST5 would be interesting if Mazda Demio (Mazda 2) and Nissan TIIDA (Japanese Versa with 1.5 liter motor) joined. Mazda Demio (Mazda 2) is very popular for Japanese rally racing and Gymkhana race in Japan now. There are many hints in Super Taikyu race cars for tuning your cars. If you could not come to Japan to see the Super Taikyu race, please come to Super Lap Battle time attack event in Buttonwillow. You can check out all the race cars and tuning cars. You can talk to the tuners and engineers about racing. I think Super Lap Battle race cars have many hints for tuning your car.