changing your box doesn't change the music, it will only change how loud certain frequencies play at given a certain amount of power input. (changes efficiancy curve).. if you want "DEEPER" then you need to listed to music with deeper frequencies in it. If you already have that music, maybe you are just looking to get those deeper sounds to play LOUDER.
If a vented box is properly designed, and installed correctly, a vented box will sound just as good as any sealed box, and it will operate much more efficiantly than the sealed counterpart... the reality, is that, a car enviroment doesn't always offer us enough space to build a large enough box with a large enough port. (with modern, "long excursion" woofers, our ports have to be much larger to manage the air flow without introducing more noise, but as you go larger in diameter, the port must also become longer to maintain the same tuning frequency.).. I'm suprised We haven't seen more passive radiators used in car applications, they are an excellent solution to the BIG-PORT problem, and eliminate the flutter accociated with the air flow of a port. With an SUV, there is plenty of space to allow for good vented/radiator designs.
If you need the space, go sealed, but be prepared to overcome the efficiancy rolloff with bigger amplification, and equalization.