Building a new box

[RooTxBeeR]

I have 2 JBL GT100d's running in series on 425 watts, from a MTX Road Thunder. I currently have a sealed box, but would like to make a ported. In the owners manual for the speaker there is a box design for 35Hz. I have all the data for the sub also. Does anyone know of a box design that would possibly be better than the one in the manual?

DIAMETER: 10" (254.0 MM)

SENSITIVITY (2.83 V @ 1 M): 94 dB

POWER HANDLING: 260 WRMS

FREQUENCY RESPONSE: 30 ~ 3,500 HZ

NOMINAL IMPEDANCE: 4 OHMS (PER COIL)

VOICE-COIL DIAMETER: 2.0" (50.7 MM)

THIELE-SMALL PARAMETERS*

VOICE COIL DC RESISTANCE: REVC (OHMS) . . . . . . 1.54

VOICE COIL INDUCTANCE @ 1 KHZ: LEVC (MH). . . . . . . . 1.22

DRIVER RADIATING AREA: SD (IN2) . . . . . . . . 54.78

SD (CM2). . . . . . . 355.00

MOTOR FORCE FACTOR: BL . . . . . . . . . 7.22

COMPLIANCE VOLUME: VAS (FT3). . . . . . . . . 2.63

VAS (LITERS). . . . . . 62.10

SUSPENSION COMPLIANCE: CMS (μM/N) . . . . 443.54

MOVING MASS, AIR LOAD: MMS (GRAMS) . . . . . 74.66

MOVING MASS, DIAPHRAGM: MMD (GRAMS). . . . . 71.46

FREE-AIR RESONANCE: FS (HZ) . . . . . . . . 27.66

MECHANICAL Q: QMS . . . . . . . . . . . 10.98

ELECTRICAL Q: QES . . . . . . . . . . . . 0.38

TOTAL Q: QTS . . . . . . . . . . . . 0.37

MAGNETIC-GAP HEIGHT: HAG (IN) . . . . . . . . . 0.31

HAG (MM) . . . . . . . . 7.92

VOICE-COIL HEIGHT: HVC (IN) . . . . . . . . . 0.88

HVC (MM) . . . . . . . 22.23

MAXIMUM EXCURSION: XMAX (IN) . . . . . . . . 0.28

XMAX (MM). . . . . . . . 7.15