91 honda prelude si 4ws 2.1?

ok, my lude wont do over 65mph, with out me haveing to go over like 3,000 rpm, then at 70-80mph its like 4-5,000 rpm. (in 5th gear.) now is that suppost to be that way, is that how the car was made, just low gearing, cuz my lude pucks up speed very fast, 1st 2nd and 3rd gear i go through real quick, but its just on the highway, i cant go fast without my rpms going through the roof! can anyone explain this? or know how to fix it if it is a problem with the car????!!!!! help!