Is a 323i chassi the same as a 328i because i have to change a rack and pinnion out of the 323i and will a 328i Rack and pinion work on this car????

I believe (depending on the year) they are interchangeable. Go to www.realoem.com and check both the 323 and 328 steering for your cars and look at the parts numbers.

It all depends on the year...
1975-1983 and 1984-1991 these are E21/30
1992-1999 they are E36 and
1999 to Current are the E90 E46