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Discussion Starter #1
This is the idea for an amplifier platform that some of you may have heard me talk about before. This allows me to mount an an audio amp inside the spare tire rim. It's a simple design, but it gets the job done.

There are two pieces - the mounting plate and the retainer board. The piece you see here is the mounting plate. The hole in the center is to provide clearance for the washer and bolt head. The wing screws attach the plate to the board underneath.


The paper represents the area occupied by the amp. Not a lot of extra room, but it fits.


With the wing screws removed, you can access the bolt without unscrewing the amp.


The wing screws thread into tee-nuts on the bottom of the retainer board.


A 3/8" driver and 17mm socket for the bolt fit where an extra bolt is usually stored in the stock foam. I have no idea what the bolt is for, but I'm pretty sure I'll never need it.


The platform will be covered with the same trunk liner carpet I'm getting for the subwoofer enclosure. The wiring will be covered in expanding wire sleeve (not wire loom) and heatshrink. I'm also thinking about using quick disconnects for easy removal, but I'm still on the fence about it.
 

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This is the idea for an amplifier platform that some of you may have heard me talk about before. This allows me to mount an an audio amp inside the spare tire rim. It's a simple design, but it gets the job done.

There are two pieces - the mounting plate and the retainer board. The piece you see here is the mounting plate. The hole in the center is to provide clearance for the washer and bolt head. The wing screws attach the plate to the board underneath.


The paper represents the area occupied by the amp. Not a lot of extra room, but it fits.


With the wing screws removed, you can access the bolt without unscrewing the amp.


The wing screws thread into tee-nuts on the bottom of the retainer board.


A 3/8" driver and 17mm socket for the bolt fit where an extra bolt is usually stored in the stock foam. I have no idea what the bolt is for, but I'm pretty sure I'll never need it.


The platform will be covered with the same trunk liner carpet I'm getting for the subwoofer enclosure. The wiring will be covered in expanding wire sleeve (not wire loom) and heatshrink. I'm also thinking about using quick disconnects for easy removal, but I'm still on the fence about it.
I like the idea of a quick removal of the amp. I was thinking something like an RCA cable attachment (not sure if those are good quality, but something to that effect) where you could just pull out and remove instead of needing tools, or needing to unscrew something.

Good work once again though!!!
 

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Discussion Starter #3

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Discussion Starter #5
I changed my amplifier selection. It will be a class D amplifier that only requires 8 gauge, so that's probably what I'll be running. I don't plan on adding to or changing my system or I'd go ahead and run 4 gauge.
 

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Thanks.

The disconnects would be something like this:

Parts Express: Featured Categories for power and ground

Weather Pack Connectors | Weatherpack Connectors | Nylon Connectors for remote turn-on lead and speaker wires. I may use these for power and ground as well. They have versions that will handle up to 60 amps (I will only need about 30).
Those look really nice! I would really consider using something like that! It seems like such an easy and convenient way to access the tire! IMO

You may have to pay a little more upfront, but I really think the convenience factor will warrant the cost!
 

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Looks like the perfect place to stash a smaller Class D amp!

How are you planning on routing the cable to the amp? Will you be simply looping it over the spare tire or will you be passing it through the amp mounting board and concealing it? Normally I'd suggest running it under the mounting board, but it doesn't look like there's any way of threading it through the rim of the spare tire. The whole thing will be concealed under the trunl floor anyway so it wouldn't really be cosmetically distracting.

I like your idea of quick disconnects...the only thing I might suggest is to run with 4-gauge cable for your power wire even if you don't think you'll need it. The larger wire will offer less resistance and will stay cooler even under full power. I might not seem like a big deal, but depending on how thick your wire is jacketed, it could be.

Once again, solid install! :yes:
 

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Discussion Starter #8
The wires will route over the spare tire. I agree that it would better to stealth them through the plate and spare tire rim, but there's just no place to do that. Everything connects to the long side of the amp toward the back of the car. I should have room to screw cable tie downs to the plate and I want the heatshrink/cable sleeve to start at that point. It will look good, even though no one will ever see it.

I may run 4 gauge wire. If I do, I'll have to find a place for a distribution block because I don't think the amp will accept 4 gauge. I think the jack area would be a good candidate since there's plenty of room and it's on the correct side of the car anyway. I can put a small (2-3 ft.) service loop in there too. I say I'll never expand, but who knows.
 

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Discussion Starter #10
I think I can put my ground on a bolt that secures a hidden bracket in the back middle part of the hatch. That would be the closest spot without drilling into the car.
 

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"I say I'll never expand, but who knows."


You can quit ANY time you want to, right ?? LOL
 

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Discussion Starter #12
Now that I read that quote, it could be taken another way as well. Oh my. I really should be more careful, lol.
 

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Nice, I am assuming the retention board is necesary to keep the spare planted in the well? As the top board the amp is installed on doesn't do the job?

Could you simply ground the amp to the retention bolt for the spare?
 

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Discussion Starter #14 (Edited)
Nice, I am assuming the retention board is necesary to keep the spare planted in the well? As the top board the amp is installed on doesn't do the job?

Could you simply ground the amp to the retention bolt for the spare?
Right. The platform doesn't secure the spare tire. It merely holds the amp and attaches to the retention board. If the amp wasn't covering the bolt, you could easily do the same thing with a single board.
 

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Okay, that was what I was thinking. I like your design though. Could you ground to the mounting bolt underneath?
 

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Discussion Starter #16
Okay, that was what I was thinking. I like your design though. Could you ground to the mounting bolt underneath?
There would be some complications due to the way I have things set up. Basically, to remove the spare tire, I need to move the amp aside. I can do this without a bunch of slack by using quick disconnects. If I grounded to the spare tire bolt, I would have to leave slack hidden under the platform or have enough cable exposed on top to allow for a quick disconnect. I'll look into it, but I think it will be easier to ground to the tie-down bracket in the middle of the back trim piece (covered by a plastic panel). I like the idea though. Maybe I can make it work.
 

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I really like the idea of the quick disconnects too. I think that will really make removing the amp to get to the spare a lot easier. You also thread two bolts on above where the retention bolt threads into the body of the car to have them clamp down on a ring terminal. I was thinking of simply drilling a hole and running the ground under the board and connecting it to the retention bolt using a ring terminal and the two bolts described above. I would then have a quick disconnect hidden under the board where I could simply lift the amp/board and associated wiring and move it to the side.

You have a great idea man and it looks really good!
 

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DOn't mean to be redundant here, if this has already been addressed...but wouldnt it be easier (especially for derrick) to put the amp directly to the left of your fabricated sub box? That seems like a nice cushy little spot for it, you wouldnt have to deal with QD's, and you could even fabricate a box for THAT if you wanted to hide it. I'm just trying to list all the possibilities here, and make things easier, because as cool as the spare tire area idea is, it could add some complications, but as long as you guys are happy, thats all that matters...See the picture below, and you will see the spot I am talking about..

 

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Discussion Starter #19 (Edited)
Chris, you know I never do things the easy way! Lol. My goal is an OEM appearance, take up as little of the cargo area as possible, and to make it removable if I ever need to haul things. It's going to be a very tame, practical system. Building on to the sub enclosure would definately be easier. Heck, I could even just screw the amp into the back of the seat. It's been done 1000 times. Those things don't help me achieve my goals though. The sub enclosure I have now is small, lightweight, and easy to remove. I can even just put it in the front passenger seat if need be. Most people can't do that with their enclosures ;) I may build something a little crazier down the road. Having a 10 or 12 with a dedicated amp would be pretty nice and all of the wiring will already be there. We'll see how this does first.
 

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For those of you that don't know Derrick ... he has a NEED to keep things clean... very clean..... Like I’m surprised he is able to drive it with the weather being so crappy lately here in Oklahoma... So him trying to say he wants an OEM look is just BS cover for his OCD!!!!


In all fairness your car looks good man, Keep up the good work with the mods!!!! Think you could figure out how to get the speed3's hood scoop on the GT?
 
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