hey guys iam in the process of building boxes under the front seats of my f30 bmw, iam going to be sealing them up as the car resonates on the low notes coming from the stock enclosure, I have replced the oem crap speaker with a helix flat piston dvc 8, and power it off a 4 channel polk audio class d amp.. 150 watts per driver, I use an ms-8 to control the sound and its 65 hz to 300hz at 24 db per oct... The box iam making will be very small as I can only use the space bmw provides for me........ so to that extent, Can someone give me some recommondations as to a good driver for this set up? either a 8 or 6.5 I don't care as long as it will play those notes in a box no more than .25 sealed.. I have lots of depth almost 5 inches. Please advise.