Can you run a 12" daul 4ohm Rtype subwoofer and a single 12" 4 ohm subwoofer off the same amplifier? And in the same car but in separate enclosures.4+4+4=1.36 ohms
Yes, but depending on how it's wired the DVC Type R is going to either recieve double the amount of power as the SVC (DVC's coils wired in parallel), or half the power of the SVC subwoofer (DVC's coils wired in series).
But technically yes, you can do it. They'll just receive different amounts of power (not a good thing)