sedan

For an FI BTL 15" fully loaded D2 in an oldsmobile intrigue.. 4 door sadan with fold down seats. . Box can be 17" tall if it doesnt exceed 30" in length and 20" in depth. Would like it to be around 3.5-5 cubes. Tuning at 28-35 hertz ideal around 34. Any suggestions welcomed!! smaller, bigger...