There's a lot of cabinet there. I'd guess closer to 40 lbs each.
And how wide is the back seat? If the speaker is 3.5' tall, I dunno that it'll fit back there either. This is what concerns me. I do think I can get at least one laying in the trunk through the back seat (if folded down). To be honest, I think this is probably a close guess at the size:
http://www.paradigm.com/products/paradi ... /monitor-9
If I remember correctly, in the v3s, only the monitor 3 and monitor 9 had the 7.5" mids/woofers. All the others used some number of 6.5" drivers. Given that, the 11v3 is probably close in size to the 9v6, since the newer 11v6 utilizes the 7.5" mids (and oddly, the 7v6 is using 5.5" woofers - I'm guessing the same drivers as either the monitor atom or monitor micro, which didn't exist when I was buying my gear).