Originally Posted by JUS_CRZN
I belive also true for e36, and you just need the enclosues not the speakers
as hes using his own.
Nope... I've got both, e36 and e46. Up until 96 e36's used 4ohms... 97+ were 3ohms. But if you have a 3ohm system, you also have a 5.25" and a 1.1" tweet in the rear shelf in a baffle box, not a sealed box with a 4" and 1" tweet.. The enclosures have different mounting points in the e46, the e36's use a single screw and a tab, unless you drill out new holes and manage to keep a tight seal.
As Paul Christians said, 6x9's also sound horrible... if they didn't, that's what home stereos and studio monitors would use too. 6x9's were invented back in the 60's when GM didn't have any room for larger speakers, so they made these 6x9's to get larger speakers in there. Unfortunately, the trend still exists today. He's much better off with 8" subs as Paul said, firing up into the old holes. This is what we're doing in the Rx8... removing the 6x9's and mounting two JL 8W7's under there instead. The hole diameter is almost identical, just have to leave a good 3" space for excursion.
If he doesn't have that kind of money to spend, then the Soundsplinter RL-i's are a very very very worthy choice, most would say even better than the 8W7's for a fraction of the cost, and matches up to specs and frequency response too. more info: http://www.soundsplinter.com/rli_ign...r_drivers.html