First of all, I'll preface this post by saying I'm new to this forum. I've been lurking for a short while after recently buying an '02 TLS. I've already found some good hints on mods that I'm planning on doing. I have a couple questions...I've searched both this forum and sounddomain.com for info but haven't found what I'm looking for.

I'm going to be putting a couple 10" subs on the rear deck (removing factory sub). I will have to cut two openings in the rear deck for this. Any thoughts on retaining the structural integrity of the rear deck? I'll just be making two ~9" holes in the metal frame, probably in the depressions next to where the factory sub is. I'm not sure if I will need to add bracing to the deck to compensate. I don't plan to hang the subs from the deck itself. I'm thinking that the subs will be right under the metal deck, installed in a sealed enclosure behind the seats (right under the deck). My other thought is to sandwich the metal deck with MDF (again, fixed to an enclosure under the rear deck). This may provide enough additional strength…I'd like to hear thoughts though. The rear deck appears to connect the two strut towers. I'm not sure if there is a factory strut tower brace. If there isn't, then this is the structural integrity I need to compensate for. So far, I haven't seen any aftermarket rear strut tower braces.

This type of install will also require gas struts for the rear trunk lid. If anyone has pics, links or write-ups of this type of setup on any sedan, I'd like to see them. Feel free to email them to me if you don't want to post…please just use an email title that makes sense so I know its not junk. BTW - I have seen systems ported through the rear deck…I'm not interested in this.

I'll also be asking some more newbie-ish questions when it comes to finding info on gutting the car. Are there full factory manuals available for a good price? Any aftermarket manuals good (Clymer, Haynes, Chiltons)? I'd mostly need information regarding wiring schematics and gutting the trunk and interior…stuff related to audio and alarm/RS installs.

A big TIA!
-K

 

why would you do that?
Thats alot more effort than you are going to get out of it. You are just going to risk fucking up your ride and if you ever sell your car, you have to get a new deck...probably.
The only person that did something similar is Austin519 hes on Acura......com
(the ...is world).

 

I have actually seen Austin519's ride on Sounddomain.com - some nice write-ups and good info. But he's porting thru the rear deck...not what I'm trying to do. Maybe I should email him though - he did cut a bit out of his rear deck...thx.

I have not yet heard a good sounding system that just plays into the trunk. IMO, you need to be in the same space where the subs are producing sound waves. But I didn't intend this thread to discuss the pro's and con's of different sub options in a sedan.

If the car is sold w/o the system, replacing the stock rear deck trim should actually conceal any modifications from the interior. You would only notice it if you looked up from inside the trunk. In any event, i'm not too worried about it.

 

very true, especially about being in the same area. Taking out the stock sub helps some, but ideally you should not have a trunk in the way.

I would think you would have to heavily modified to support the weight and movement of two subs. Considering it wasnt designed for it...If you pull it off we would all love to see the results.

What about the stock sub? are you going to leave it in there, or use that hole also? Might as well put 3 10's...

 

The subs weight wont be resting / hanging on the rear deck. The enclosure under the rear deck will go right to the floor of the trunk. Basically think of it like this: if I cut out the entire rear deck and just put a sub box facing up...with the subs at the height of where the rear deck used to be -> thats what it would essentially look like. But is much more complex to get that to happen. And it wouldn't make sense to chop out the whole rear deck (in my case anyways).

3 subs is overkill for what I need, not looking for a peak SPL. I just like bass clean and powerful, but not blow my windows out...I don't need to hear it from 3 miles away.

I'll definitely have a bunch of pictures of any install I do. I belong to another forum for my SUV, we shared lots of good info over there...probably one of the best run forums I've been on.

Thanks for the interest...I can't wait to get started working on my new ride.

 

ok i totally understand how you feel about the subs being in the listening area... but i would not cut two wholes in the rear deck to acheive that.. i think that you will acheive the same sound by porting your subs thru the existing opening as austin519 did...

 

actually Austin cut his deck and ported them through new holes.

 

Definitely not the same thing...not even close actually. His subs seem like they will act somewhere between a free-air and bandpass enclosure. I haven't seen anything like this before (not knocking it, just never seen it before - he is not using a standard type of enclosure). I'm not sure how he's going about calculating proper enclosure and vent sizes...seems like a very complicated task for his design and definitely not something I would want to try to do.

I just want my JL subs in a sealed enclosure firing w/in the listening space. I could just put the sub box on the rear seat, but that would defeat the purpose of having a rear seat. Maybe I should've bought a 2-door and just junked the rear seat. In any event, I've done some thinking on how I want to go about doing it and it shouldn't be too bad (knock on wood).

No one out there has info on using gas struts to support the trunk lid??

 

serriously I have both my subs in the trunk and I took out the stock sub to let them vent some. The sound is perfectly fine - loud and clear. I just dont think you will be able to hear much of a difference if any.

 

I will definitely give that method a try before I do anything. How is the enclosure oriented and located?

 

Don't post much anymore but since you show a sense of adventure, I'll post my experience.
I once ran a 8" sealed MS-80 sub attached directly to the bottom deck and installed gas struts to make up for the loss of the torsion bars. Nice, crisp, non-originating bass, excellent SQ but not much SPL. Trunk mounted sealed subs just can't get that last 10% SQ, IMO, and I'm all about SQ. I eventually wanted a change and removed the above system and went straight to a sealed 12" sub in the trunk(I got lazy and moved on to another project). I will say SQ was much better when the sub was sealed in the cabin, no doubt. You end up not creating mechanical resonance which is critical for clean bass.
Anyways, back to your install.
I mounted the gas struts from rear shock pillar to the curved trunk hinge. It took about 60-80lb struts with a long stroke to get the trunk to operate normally. Problem was, with that high of pressure, when the trunk was closed, the struts pushed up on the trunk so the leading edge was up about 1/8" above the rear fender line. Only noticable up close, but still I noticed it. If I now know what I knew then, I would have mounted the struts in the rain channel on both sides of the trunk; going from the rear fender rain channel to the trunk lid (similiar to the hood mounted struts) and sealed it extremely well.
From what you are describing, I would highly recommend that there be NO gap between your sealed box/sub and the bottom of rear deck. You want this to be airtight along with the rest of the rear deck. You can install a closed-cell foam collar around each sub to accomplish this, but must provide pressure upwards against the bottom of the rear deck to maintain a tight seal. You can mount the sub box on a stiff base and use jacking screws to provide pressure upwards.
But, I wonder why you are willing to cut the rear deck but use a sealed system. Why not mount the subs IB in the rear deck and seal the trunk. This would provide excellent SQ and decent SPL, reduced amp power, less weight on the rear deck, while leaving more trunk space. Or (1) high quality 12" sealed directly into the cabin would be more than enough, IMO.
Either way you choose, good luck and have fun.

 

Awesome input brewboy, thank you very much! The info on the gas struts is helpful, I wouldn't have guessed going that high w/ the strut force.

 

Here is the picture of my subs in the trunk.