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OP, it would be a monumental waste of space, money and time to do different style enclosures in the same vehicle. Like previously stated, the resonant frequency of a ported box and a sealed box of the same dimension is going to be different. The ported box is going to overwhelm the output of the sealed box, but thanks to the different resonances, each wave will cancel one another out. You will actually have less output, crappier sound and equipment longevity issues than doing a traditional sealed or traditional ported enclosure.
If you are looking for the best of both worlds, build a low tuned ported enclosure using quality "SQ" oriented subs (ID, JL, Morel, *certain lines from plenty of other companies*), a quality amp (JL Slash, Kicker SX, ARC, Audison, etc) good RCAs and a nice "SQ" deck (99PRS, 80PRS, Clarion 71**). A good signal system (HU, RCA, Amp) combined with a proper enclosure will ensure accurate and non-coloured tonal response. Any sub could actually sound great like this, but some of those named are less output oriented with better specs for what I think you're wanting.
Don't, I repeat, don't do what your OP speaks of unless the sealed sub is on its own amp and is completely crossed-over to play a different set of frequencies from your ported sub. Ex. Ported Subsonic~63hz Sealed 63~100hz