Help with measurents to build a Bandpass box for a PowerBass L-124D

Hi everybody, well, like the tittle say, I have a PowerBass L-124D that I want to use in my car, I have a hatchback, so I think that the best box is a bandpass, or is what I want, I need you expert help to let me know what measurents of the box I need to build my box. I will like the hertz cut around 30hz to 40hz

This is what I have of the sub

Size: 12in

Power Handling

(RMS/Peak): 400/800 watts

Nominal Impedance: Dual 4-ohm

Voice Coil Size: 2 in

Frequency Response: 24Hz - 400Hz

Sensitivity: 92dB

Motor Structure: 180 oz

Mounting Depth: 5.4 in

T/S Parameters

VC Impedance: 4 ohm + 4 ohm

Test Impedance: 1.6 ohms

Fs: 29 Hz

SD: 471.4 sqCM

Vas: 59 Ltr

Cms: 207 µM/N

Mms: 141.5 g

BL™: 11

Qms: 5.2

Qes: 0.54

Qts: 0.49

No: 0.218%

Spl: 92 dB

Xmax: 9.5 mm

Thanks a lot for the help...