picked up a pair of compvr 8's, what size ported?

[Ridinhi]

got a set of mint compvr 8's. Think these came out in 2002. Black cone with kicker comp in Red and VR in yellow. Had good luck with this model in the past so i picked these up. What size Ported enclosure should I build? Giving the pair 500watts. Would sealed be an option? Goin in the back of my 02' Maxima(seats fold down)

[DbDesigns]

run them in an IB setup...