Phoenix Gold Phorum

Thanks for all the help so far guys but I have 1 more question before we chop up some wood and tear the truck apart on Sat. I am using an RSd12 and going to feed it about 700 watts (going to use a Directed d2400 instead of the Avionixx 1200 I have). With plenty of power in a sealed box should I shoot for something around 1.2 cu ft or stick with the 1.8 a couple folks have suggested?

Set up I ended with is
RSd6.5 comps in front
Crossfire CFA 354 at 150x2
1 RSd12 sealed (needing help on size)
Directed D2400 (rated at 800x1 but at 14.4v)

Thanks for any input given.

1.8 for RSD (silver cone)
1.25 for RSD competition (black cone)