I haven't gutted the trunk area of my X for a few months, but if we're talking about the same thing and making an enclosure similar to the size of BSW's, then you could make your own enclosure and put it on either side since you're ditching the factory setup. I removed the factory amp and rewired all 14 speakers locations in my 740iL...it was hell, but I got it.

You mentioned that you're planning on keeping the factory deck so you can use the steering wheel stereo controls, so I don't know how you plan on being able to do that, unless I missed something. I'm not sure how the tuner works, if it's independant or intergrated into the stock deck since I'm bone stock in the X and completely custom in the 7.

The electrical system in BMW's have and always will be hell, but I haven't had any problems in my 7. I run a 1500watt monoblock MTX 81000D amp running a single DVC RE Audio 12" in a huge box, no cap, and it runs w/o a problem. It's convenient that the battery is located in the back, so your amp will love the short current path of power. I'd just make sure to use screen 7 (I think) on the OBC and monitor the battery voltage if you suspect your system is giving you gremlins after you get it up and running. I still run the factory BMW battery in the X, but the 7 had a Duralast (Autozone) 69D (I think) battery...similar CCA and size, longer warranty and only cost like $90.

thanks again,
I'm using something from rockford fosgate called the 3sixty.1 here's the link: http://www.rockfordfosgate.com/products/product_details.asp?cat_id=1&series_id=49&family_i d=50&item_id=106185&locale=en_US&p_status=[/URL]

It will let me take the signal from the head unit sum up all of the cut frequency's and process them via a laptop add on program so that I can send a clean pre-amp out signal to my aftermarket amps. The cool thing about this thing is I can adjust the levels of each individual speaker via a laptop....pretty cool....

As far as the enclosure goes, I've made up my mind to go with MDF, I'm actually creating a template for the front cover while I'm writing this. The spot I am referring to is the plastic piece located under the floor cover that is held in by 2 plastic 10mm nuts. I plan on making a flange on the bottom of the front face of the enclosure and drilling a couple of hole to utilize the bolt posts that come out of the chassis. I'm guessing these along with the two bolts at the top (the ones that hold the fuse box on the pass side) should be enough to secure the box. I'll let you know how the mock-up I'm currently making works out. Will send pics if it works , when its done....:doh:

Damn bro, that thing looks like it could be fun or a headache. Keep us posted for sure. My box is basically a custom made version of Zero's custom box, just made larger to fit super tight and to use up the space from where the fuel door locking mechanism was.

Sub Upgrade to 10" using factory amp?
 

Does anyone know the facotory amplifier's power output (watts) to the subwoofer? My '05 has upgraded sound with DSP, sounds good, except the bass from the factory 2x 6.5" subwoofers is a little light, I was thinking of modifying the factory sub enclosure to house a relatively low power dvc 10" subwoofer, driven by the factory sub amplifier ouput. If that works, great, but if the oem amp can't power the sub properly, I can always upgrade to an after market amp at a later date.

Any thoughts?

Don't know the power rating on that but I'm sure a decent aftermarket will provide much better output, especially since the factory is only pushing 2-6" drivers. The 10" will need significantly more muscle to move it properly.

Getting back to the enclosure I was making.........MDF is simply not an option if you want to maximize the space in the rear cargo holds and use a normal sized subwoofer . It doesn't make any sense to me to go through all of the trouble to create a sub enclosure for a slim mount if the net gain isn't all that much. Therefore, I've succumbed to making a fiberglass enclosure (first one) but it's gonna have to wait until the temps warm up a bit.

Some have just taken the stock enclosure, cut the face off and fiberglasses a piece of MDF on in order to mount a 8"-10" sub. Many people keep asking about going up to a 12", but a good 8"-10" in the right airspace will always sound better than a 12" in too little airspace. If you're going to go through all the trouble, just pick up a nice 300 something watt monoblock amp like I did for $80.

I've only completed half of my enclosure using think cardboard to make a template, but it's definately going to be creative trying to make it as large as possible and routering the edges so I can still slide it in and out. I've considered using a plastic bag and expanding foam to give me something to mold fiberglass too, but I haven't decided if I wanna try that yet.

Actually James,
I've already got all of my gear. I've got a jl 500/1 to power a jl 10w6v2D4. Xtant A4004 (Bridged) to power my front's DLS iridium 6.3's, PPI (old School A404.2) Bridged to power the rear's. I'm keeping the factory head and using the Rockford 3sixty.2 as my LOC. I've also removed the CD changer in favor of a spec.dock 2point5 (ipod in the ashtray). I've got to get this damn sub done first.......Cool thing is I've found that I can use the factory mounting brackets so the glass box won't rattle. Unfortunately, I'm looking for a heated garage I can use for a couple of days to do the glass work. none of my friends want me stinking up their spaces:(. As I said I will post pics when we get started. BTW do you know if removing the stock amp all together will screw up the AM/FM tuner and antenna? Non DSP/non NAV

James, don't use the foam!!!!!!! I tried an experiment last week and what a disaster.... The foam needs to be in contact with the air to harden. Therefore, the outside of the foam hardened and the part against the car did not harden after 3 days...... I used plastic bags and duct tape and it was still a major mess. BTW make sure u use gloves with that stuff....it doesn't come off once it dries.