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Discussion Starter · #1 ·
After 4 years of driving this car (almost daily) I figured it should be worth the effort to upgrade the audio system.
Till now I had an old Kenwood HU with cd changer (10 disks) connected to 2 door speakers (I don't even know what make those are, haven't looked yet :surprised:)

The plans are:

Pioneer P88RS II HU
JBL GTO 504 Amp (2x 55 for fronts, 1x 140 for sub)
Pioneer TS-E170Ci component set in the doors
JBL GTO 804 sub in the front trunk

The plan is to put the sub in the trunk space known as the smugglers box. The reason for this is the car gets used from time to time as a family car with my girlfriend and son riding with me. So I can't give up space in the cabin to gain some bass.
On the Porsche forum I visit (pelicanparts) I had seen the use of the smugglers box for a sub so I figured why not try it. It's in the front and it's unused space so it's worth a try...

Lets move on to the build. First let me introduce the car, an '82 911 SC:


Moving on to the trunk of the car we find this:

The smugglers box I mentioned. I think in most american models you'd find some airco stuff in there but mine is almost completely empty.

So I went to work with cardboard templates and rulers and started hacking up some MDF. After trying to fit 2 pieces for front and rear of the sub box made of 3/4" MDF I discovered the JBL sub wouldn't fit between them. So back to the drawing board. Although not optimal I choose to go with 1/2" MDF for front and back and the rest with the thicker stuff. Here's what I came up with:


I put in a brace to strengthen the weaker MDF parts...

On the baffle I used t-nuts to mount the 804. I've drawn the sub in a 3D program to figure out the size of this thing. JBL says the 804 needs about 8.5 liter. My calculations/drawing gave me a little over 9 liter after bracing the box. Not bad I think?

It's a tight but good fit:


That's as far as I am right now. The box is in paint and I'll report back when I complete the next step(s).
 

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That garage...oh my :surprised:

How much sound makes it through the front firewall? Or does the "smugglers box" kinda vent into the cabin?
 

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Finally, another 911. Maybe I can feed off your install and get
some stuff done also....

I've only seen the sub fired into the smugglers box never done
like this. I'm really interested in your review once finished.

Welcome to the forum
 

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Discussion Starter · #7 ·
Thanks for all the reply's and the welcome...

As far as sound comming into the cabin? I don't know how well that works yet. But I've seen similar setups that claim to work well. Those threads inspired me to try this. Let me trow in the links to show their solution:

Sub mounted in spare wheel well
and
Sub in smugglers box

However that last one uses the smugglers box as a chaimber by sealing part of it off. The inner wall of the smugglers box can be seen in the cabin. Mine is a sealed box thus the sound will have to travel trough the fire wall. But there are many ways for the sound to enter the cabin for example trough the heating system pipes etc.

So my setup will be different yet similar to the first one sound wise. I can't wait to try but it will be a while before I have sound. I don't have time in the comming week to continue.
The next step is to mount the amp under the passenger seat.

I haven't made up my mind yet about sound deadening. The doors are done pretty good from the factory but the trunk lid has none. I think it will need at least a bit of vibration dampening. Time will tell.
 

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Discussion Starter · #8 ·
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Looks great.

If my mind serves me correctly, we built a pretty sweet setup back in the 90's for an '87 935 that used a Nak SP-1010 in a free-air bandpass config. The enclosure set over the left front wheel well in the baggage area using the trunk as the large sealed section and a 3 in flexible port that ran from a 1 cuft enclosure through the firewall and porting into the cabin under the clutch or brake pedal. It was not a monster, but would play the low end like crazy. Looked effin cool to boot!!
 

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Thanks for all the reply's and the welcome...

As far as sound comming into the cabin? I don't know how well that works yet. But I've seen similar setups that claim to work well. Those threads inspired me to try this. Let me trow in the links to show their solution:

Sub mounted in spare wheel well
and
Sub in smugglers box

However that last one uses the smugglers box as a chaimber by sealing part of it off. The inner wall of the smugglers box can be seen in the cabin. Mine is a sealed box thus the sound will have to travel trough the fire wall. But there are many ways for the sound to enter the cabin for example trough the heating system pipes etc.

So my setup will be different yet similar to the first one sound wise. I can't wait to try but it will be a while before I have sound. I don't have time in the comming week to continue.
The next step is to mount the amp under the passenger seat.

I haven't made up my mind yet about sound deadening. The doors are done pretty good from the factory but the trunk lid has none. I think it will need at least a bit of vibration dampening. Time will tell.
Looks great.

If my mind serves me correctly, we built a pretty sweet setup back in the 90's for an '87 935 that used a Nak SP-1010 in a free-air bandpass config. The enclosure set over the left front wheel well in the baggage area using the trunk as the large sealed section and a 3 in flexible port that ran from a 1 cuft enclosure through the firewall and porting into the cabin under the clutch or brake pedal. It was not a monster, but would play the low end like crazy. Looked effin cool to boot!!
Hmmm...wonder if an infinite baffle sub could be installed in that way. Have the magnet hang down into the space and use the trunk as the box. You'd just have to reverse the polarity on the sub.

I want one of these 911s someday and I'm a fan of IB so... :D
 

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Hmmm...wonder if an infinite baffle sub could be installed in that way. Have the magnet hang down into the space and use the trunk as the box. You'd just have to reverse the polarity on the sub.

I want one of these 911s someday and I'm a fan of IB so... :D
Not really a need to reverse the polarity on the sub, unless after testing it is deemed necessary. But that is essentially what was done with the Porsche we did back in the day, and now that I think of it...it may have been the Nakamichi 8". But the magnet did hang into the trunk with the cone facing into the box..
 

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Discussion Starter · #14 ·
I'm glad I named the thread "simple system" :D
I'm going to stick to the sealed box for now (lol)
 

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Discussion Starter · #15 ·
your garage looks cleaner than my house...:D

awesome car, looking forward to your install ;)
Here's proof my garage doesn't always look that clean :D

 
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Discussion Starter · #17 ·
time for an update

I've been away on holliday for a week so it's high time to get going again. The car has to be back on the road next week.

Here's the sub box painted and ready for install:


Next step, sub in the car...


and the carpet back in place:


On to mounting the pioneers in the door. First step was making a new mounting baffle, lucky for me someone on the pelican boards had a ready to cut sketch so I used that as template.



Here's the empty door with the standard cutout from factory:


This is what I pulled out of the door, no wonder it didn't sound that great anymore. Half of the time the speaker would rattle against the door card. The cutout in the door card was a lot smaller than the speaker. The speaker itself was attatched with 2 screws.

They are Pioneer TS-1745 17cm speakers (35 Watt RMS). I had expected to find some old blaupunkt 5 1/4" speakers as it came from the factory (I think).

In with the new baffle:


And with the door card back in place:


Too bad I have to pull it back out again to paint the baffles :(
Tomorrow I hope to make some real progress...
I plan to mount the tweeters off axis somewhere between the window switches (on top right) and the 6.5" driver. The crossover will be mounted
in a (sealed) compartment below the door handle. You can see the shapes a little to the left of the driver. I still need to pull new wires, add some vibration dampening, there's none behind the speaker so I'll add a tile and on top of that some kind of diffuser pad. Tried to order it tonight from the UK but that failed, hopefully I'll get the order going tomorrow.

Till next time...

Wesayso
 
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Discussion Starter · #19 ·
Thanks! You're right, Porsche mounted it there so it seemed the obvious choise.
I'll concider running an extra pair of wires to be able to go active with this setup later on if I want to.
 

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Great build - thanks for sharing!

As a fellow p-car owner and Pelican I was wondering if you might share your smugglers box enclosure dimensions... as I'm working on a similar set-up for my '70S.
 
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