Now I bought a rb25det awd, I was told it was a neo and came out of a stagea. but it has alot of s1/s2 stuff on it. I.E. the injectors (black plug), vtc. (black plug) and o2 sensor (grey plug). but has the Hitachi (black plastic) CAS. This is the serial number RB250165a located on the rear exhaust side of the block. I've searched and searched. Need some fellow input from people with actually experience with rb25det's neo and non neo.
P.S. I've also heard there is such thing as a series 3 (RARE)? which is a series 2 but with a neo exhaust cam and timing covers