what exactly are your options? i HATE the 4.2 i would only take it in 87-88 because the 2.5 only had 83 HP after that the 2.5 has more HP than the 4.2. even though the 4.2 had more tourq, they would tie in a drag race, and the 2.5 would be much nicer to drive. of course if you had the choice of a 91+ 4.0 get that.