So my friend and i have been search for a catback for his 95 LS 4dr and only seem to come accross the apexi N1 exhaust. Anything else we find that would work on a 4dr is for the gsr. He wanted to the RSR exmag but they dont make it for a 4dr. Whats the big difference between the 2and 4dr exhaust? Anyone have any ideas? Thanks.