well, the E36 326 is from 1992 to 1995 while the 328 is from 1996 until the E46 got out....they're more recent(that's why they're more $$$)
and the peak torque on a 328 is achieved at a lower RPM then a 325
doesnt the 328 have VANOS? I always thought that was the main diff(apart from the bigger displacement). and didnt the first 323 have the old 325 engine when the 328 came out?? BMW guys give me the facts!!