[stretchsje]

The spare tire well is neither a circle nor a square- the edge along the rear of the car is a shape of swervy metal and goo, and the tire is in a semi-circle inset within a thin, rectangular frame that holds a plastic cover. The bottom is full of divets, as are the sides. What a mess!!!

Nonetheless, I'm going to try to use the spare tire well as a subwoofer enclosure. I have it all mapped out- my subwoofer will fit, protected, and I expect it will even sound good there providing I can find a way to air-tight the box. This will only work if I air-tight the box, but that's going to be the hard part! The actual well is ~26" accross with a rise in the center, making a center mount impossible. I'm going to put the subwoofer into the top quadrant (between the rear seats and the center of the tire well); and try to use the center protrusion as a brace. This will move the subwoofer far away from the rear of the vehicle, which is were I expect to have sealant problems. If I find it impossible to seal the rear, I will try to create sort of a slotted port, and its hould behave like a ported woofer enclosure. Total volume should be 2ft^3, at least, so a ported enclosure is actually preferable.

This means drilling many holes into my trunk (out of site and away from the underpinnings of the car- it's safe) to firmly attatch the baffel in place, and I haven't yet figured out what kind of substance I'll use to seal it. This baffel must be removable, and most foam or caulk sticks like glue.

I bet that this is very hard to picture. Nonetheless... any suggestions before this project gets underway?

Weight savings from losing the spare tire and subwoofer box should be at least 50lbs, and I get my trunk space back. Any suggestions for a cheap fix-a-flat kit? Guess I should buy one first- I assume Pep Boys or Auto Zone will have one for $20 or so.

 

[kyler13]

Reading Topic: 12

Not a bad idea. I talked to a shop up here in Columbia about doing a spare wheel well custom enclosure. They make it out of fiberglass for free-form function and weight savings. That would give you the most optimal volume with the lowest profile. A tire-pressure monitoring system from Tirerack might be a good idea. That way you can see slow leaks before the tire runs down to almost no pressure and get to the nearest shop for a repair.

 

[SDSilver6]

Replying to Topic 'Spare tire subwoofer'

QUOTE

Originally posted by kyler13

What governor?[/b]

Kyler, just curious.... did you actually snap a photo of your speedometer while driving 135 mph?????

 

[(Atenza)]

Reading Topic: Spare tire subwoofer

Please take some pictures for me when you are working with the spare tires sub

 

[kyler13]

Replying to Topic 'Spare tire subwoofer'

QUOTE

Originally posted by SDSilver6


            QUOTE

Originally posted by kyler13

What governor?[/b]

Kyler, just curious.... did you actually snap a photo of your speedometer while driving 135 mph????? [/b][/quote]

Well, now, you know the good ol' ECU won't let us above 120mph, and my speedometer is reading 140 mph SO I must of caught a 20 mph tailwind.

 

[djmn]

Replying to Topic 'Spare tire subwoofer'

Anybody know of a way to "enclose" the subwoofer from the Bose stereo package? Instead of just upgrading the 9" sub to a good quality 8" IB subwoofer, I was wondering if there would be some practical way to create an airtight enclosure using the existing area in the the back window well.
I'm real suspect about the trunk being able to support a Free-air sub without any low end cancellation. With the fold down seats, there's no way that thing could be anywhere close to airtight.
Anybody thought of doing this? You wouldn't have to mess with the spare tire well that way.

 

[kyler13]

Reading Topic: Spare tire subwoofer

Without knowing critical info about the sub, I'm not sure you'd be able to do that. I think you'd be better off buying an aftermarket sub and building a lightweight enclosure that could be bolted up underneath the rear deck (I think I mentioned this before in some other thread). Of course, that would best be left to a professional stereo installer.

 

[Entropism]

Reading Topic: Spare tire subwoofer

The bose sub was designed to run the way it is. Adding an enclosure would either A: destroy the sub or B: kill the sound completely.

An IB sub like the BOSE's are used because they're very efficient. Adding an enclosure would reduce the volume by (an ESTIMATED) 50-75%.

 

[djmn]

Replying to Topic 'Spare tire subwoofer'

Sorry,
I should have been a little more specific...I want to do what kyler13 is saying...add an aftermarket sub (not an IB) and create some form of enclosure attached to the rear deck.
I was just wondering if anyone has tried this or has any good ideas about how to go about this...the underside of the rear deck is not flat metal so designing a box might be a little tricky.

 

[kyler13]

Replying to Topic 'Spare tire subwoofer'

QUOTE

Originally posted by Entropism


            The bose sub was designed to run the way it is.  Adding an enclosure would either A: destroy the sub or B: kill the sound completely.

An IB sub like the BOSE's are used because they're very efficient.  Adding an enclosure would reduce the volume by (an ESTIMATED) 50-75%.[/b]

Reduce it?! It's already TOO low! As I stated before, the door speakers put out more volume in the low frequency range than the sub. Cranking the volume or increasing the bass to try and get more out of the sub results in terrible distortion in the door speakers.

 

[Entropism]

Reading Topic: Spare tire subwoofer

Riiiight... I don't understand why you're so surprised. BOSE sucks, simple as that. You were expecting to win soundoffs with the stock system? Frankly, I'm pleasantly surprised with how good it DOES sound, as compared to my usual BOSE experiences.

DJMN, Can I suggest something that might help you out? JL Audio makes excellent IB subs, as does Image Dynamics' IDMax. The Max is expensive (about $300) and eats power for breakfast, but it's the best IB-capable sub on the market right now. Just remove the BOSE sub from the rear deck, and put a panel across the back seats, and mount the sub there. If you want to use the rear deck, then get out the snips, void your warranty, and put in a JL IB10. It'll certainly be an improvement over the BLOWS system.

 

[kyler13]

Replying to Topic 'Spare tire subwoofer'

QUOTE

Originally posted by Entropism


            Riiiight...  I don't understand why you're so surprised.  BOSE sucks, simple as that.  You were expecting to win soundoffs with the stock system?  Frankly, I'm pleasantly surprised with how good it DOES sound, as compared to my usual BOSE experiences.[/b]

The stock sound system in the Supra was the same set up (but not a Bose system) with 6 speaker + subwoofer. At least that system actually had the more of the bass coming from the dinky sub. I can't understand how a company that specializes in audio can not properly balance a system with a subwoofer. That would be like home theater receivers still sending the LFE channel to all 5 speakers in addition to the subwoofer.

In any event, I may be too discriminating. It actually does sound pretty good for a "from the factory" system. It still doesn't touch the system in my Honda that, in all honesty, isn't the best equipment or the best set-up. Certainly wouldn't win any competitions, but it's so much more pleasant to the ear. Oh well. Project time!

 

[stretchsje]

Reading Topic: Spare tire subwoofer

I bought the wood for my project today. I have the measurements and plans.

Tomorrow I'm buying a jig saw... I'm young and still accumulating tools as I need them

 

[alpine6]

Reading Topic: Spare tire subwoofer

Good luck on the sub enclosure, can't wait to see the pics, 2ft^3 is alot of air space, what kind of sub are you putting in. I guess that is not to much for a ported box though. I wanted to put an amp rack in the wheel well, but the wife says no way.

 

[Se7en]

Replying to Topic 'Spare tire subwoofer'

QUOTE

Originally posted by kyler13


            QUOTE

Originally posted by SDSilver6


            QUOTE

Originally posted by kyler13

What governor?[/b]

Kyler, just curious.... did you actually snap a photo of your speedometer while driving 135 mph????? [/b][/quote]

Well, now, you know the good ol' ECU won't let us above 120mph, and my speedometer is reading 140 mph SO I must of caught a 20 mph tailwind.

[/b][/quote]

where can i catch a 20 mph tailwind?

 

[84FordMan]

Reading Topic: Spare tire subwoofer

Ride behind a semi? Or a car going equally as fast? That's how the guys in NASCAR do it.

 

[stretchsje]

Replying to Topic 'Spare tire subwoofer'

http://www.cardomain.com/member_pages/view...d=337907&page=2

I installed a 12" subwoofer in the spare tire well today. I'm still waiting for some expanding foam insulation to dry before I can trim it down. While I wait...

Take a look at the first picture. A 12" subwoofer is the largest that will fit, and even then mounting depth may be a problem. I installed the subwoofer on the top end of the trunk, as a center mount is impossible due to a bulge in the well. That bulge, however, is extremely important- the screw used to keep the spare tire in place is also used to keep my subwoofer in place. In the rear of the car, the well has many, many curves, but I did my best to create a piece of wood that outlined the rear of the car and I mounted that to my main baffel. I'm sure it isn't air tight, but the rear should act somewhat like a speaker port.

My baffel was 28 1/2 inches wide and a little over 28 inches long. I cut the sides and front at a 15 degree angle to coincide with the slope of the well (which is more like 30 degrees, but I wanted space for my foam). Since this baffel will bear weight when the trunk is full, cutting an 11" hole for my 12" subwoofer was not an option. Instead, I cut a design, with the largest hole being 2" in diameter in the center. It's a poor design, and isn't what I had originally planned. Nonetheless, it lets an adequate amount of air through and still will bear lots of weight above.

Since I mounted the subwoofer directly against the bottom of the baffel, the woofer surround laid up against the wood. This completely prohibits woofer cone movement, so I used a router to bore out room for the cone to move. I bore out 2 layers of the 5-ply, 3/4" wood, about 3/8". I calculated this to give me nearly half an inch of woofer excursion, which is more than the Xmax of my relatively inexpensive Infinity subwoofer.

Once the woofer, baffel, and back was assembled and glued, I put it in place and ran this expanding foam all around the edges. I really used a lot to ensure no rattles. The foam dries hard and can be sanded and cut. I will need to cut it once it dries to get a nice smooth, continues surface, and I can furthermore cut it again if I ever need to remove the subwoofer (and repair/replace it). Not an elegent solution, but my best one.

The sound is fantastic- much better than my box. The gain is incredible since the back of the enclosure is the car- steel, not plastic. Not only is their massive gains from this, but despite the gains it does not sound boomy- at all. The steel enclosure is rigid enough to give me nice, clean bass that fills the cabin.

All in all, I'm pretty pleased.

And, in case you forgot what my car looks like...

 

[stretchsje]

Reading Topic: Reading Topic: Spare tire subwoofer

Oh, and sorry 'bout not getting more pictures of the baffel prior to installation. I tried, but the camera died on me every time tried to take a picture- dead batteries. I was running out of sunlight, so I went and did the final install before hunting down some batteries. I hope I described it well enough- the part you DON'T see is definately the important part.

 

[DennyA]

Reading Topic: Spare tire subwoofer

So you're just riding without a spare? Livin' on the edge, eh?

Of the three flats I've had in 21 years of driving, "fix-a-flat" would have only worked on one of them.

And it certainly wouldn't have helped when someone stole a tire and all four lugs off my Chevette... Had to put the donut spare on and steal a lug from each of the other wheels.

If I were you, I'd toss that donut spare in the trunk when you don't need the space to carry something else.

 

[stretchsje]

Replying to Topic 'Spare tire subwoofer'

QUOTE

Originally posted by DennyA
If I were you, I'd toss that donut spare in the trunk when you don't need the space to carry something else.[/b]

I plan to do this for any long trips. Living in an urban area, most places I drive to are within 6 miles (walking distance) of my home if I must, plus I have a cell phone.

Really, I was persuaded mostly because of Mazda's use of fix-a-flat in the RX-8.