I have a proton Gen 2 which I bought from a friend. when he bought it before it was already running on a 4G92 mivec engine. so both of us did not know what type of 4G92 it was specifically. I've did some research, probably it's a CJ4A or a CK4A. I'm confused. characteristic of the engines is, Mivec change over at 6800 RPM. I've check the ECU code which is 2556. however, I was told the engine is a 4G92 mivec RS.