Box can be as large as 4 cubes,5 if it on the rear deck and in the well. I drive a 95 pontiac firebird.I will de useing a directed 1500d(untill I buy a 2400d) Will be useing a 1ohm load if I buy the 4 ohm dvc's if I buy the 2ohm dvc's I be running a .5 ohm load. The box will be tuned at like 50...