EK 4 vs EK 9 EK is basically a chassis code, and the different numbers 4 and 9 refer to the different models. While EK 4 and EK 9 may seem similar, there are differences between the two. When comparing the two chassis, the EK 4 is equipped with a b16a DOHC VTEC engine, and the EK 9 comes with a b16b DOHC VTEC engine.
