My Custom 8” sub box that clears fold flat floor

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blackbetty14

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What is the approximate depth you have with the box?

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What is the approximate depth you have with the box?

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I have 5” depth from the bottom of the box to the underside of the MDF board. So 5.5” from the bottom to the top surface of the top MDF board.
 

OC455

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I want to say about


I have 5” depth from the bottom of the box to the underside of the MDF board. So 5.5” from the bottom to the top surface of the top MDF board.

Awesome....was looking at some Diamond Audio shallow mount sub/subs. I thought I had a blown front speaker this morning when I cranked up my radio....still could be, but didn't look to far into because I had way too many other things happening tonight.

Looking to upgrade again. I'd hate to lose the storage but, getting some better sound would make me happy.
 
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blackbetty14

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If the sub is less than 4-5” you should be fine. Just match the sub to the amp and your expectations lol.
 
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blackbetty14

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Ran the 8 gauge power wire tonight. Tried a few different ways but decided to just drill that clutch block Off plate on the firewall. Wire is run to the back and I mocked the Alpine MRV-M250 but putting 2 strips of Velcro on the bottom, sticks to the carpeted floor and holds it enough where it won’t slide around. Lots of room, and will let me pull the amp out easily (Velcro) to connect/disconnect amp wiring.

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blackbetty14

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Finished everything up today. Pulled the stock sub to tap into the sub terminal for the LOC signal. Removed the sub, removed the bolt blockoff I put in and used a grommet with rtv for the speaker wire to go through. Tapped into one side of the DVC and ran it out over to the other side and connected both LOC channels to the wire as they are single channel. Set the amp gain to nominal and bass boost at 0. Sub hits a good bit harder than the stocker and this is with a new sub that still needs to be broken in.

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blackbetty14

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Hey guys. Decided to get myself an early xmass present. It was clear I was maxing out the pioneer 8” with 150-175rms and would hear it at higher volumes with the gain at NOM (1/2 way). I went on the search for a better 8” sub to handle the power while being shallow and fit the space. I thought I was cool with the JL 8” but that was also rated at 150rms. About 20min talking to crutchfield they confirmed that it would be around the same predicament I was in. They recommended a few but I decided on the kicker compact 8” shallow. It’s a dual 1ohm voice coil so wiring in the same as my pioneer would put me at 2 ohm which my amp can safely handle. This bumps power from 150-175rms @4ohm to 250-300rms @ 2 ohm. The kicker sub is rated for 300rms at its sweet spot so it would work well. Ordered and installed today. I also decided to add some polyfill to the boxes to help with the smaller box sizes (sticker and custom). I didn’t add a whole lot but stuffed the bottom and sides. Installed and had to Redrill the subs mounting holes and find hardware to fit. Crutchfield was priced the same as everywhere else as they had the kicker holiday sale saving $37 or something so the sub was $112 shipped. The pioneer was only $60 shipped, but if you ran the pioneer with 100-125rms it would be perfect!

Cranked it up and man it hits with another 150rms compared to before. I actually lowered bass on the stock eq to +1 and I’m letting the sub break in. But I had volume up to 28 with no distortion. My Sirius just ended a few days ago and I feel like the sound was louder before with satalite vs FM so it’s not Apple to Apple comparison. Seems like a nice improvement.

Side note the quality of the kicker sub is nice, heavier than the pioneer and it’s all once peice (grille is attached to the sub) but I was annoyed that kicker didn’t supply screws.

Pics of the new sub!

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Thats an awesome job! Looks professional! You sound pretty educated on system setups. What would you recommend if i just wanted to upgrade the factory sub that i have now?
 
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blackbetty14

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Thats an awesome job! Looks professional! You sound pretty educated on system setups. What would you recommend if i just wanted to upgrade the factory sub that i have now?
Factory sub for a drop in replacement would be the pioneer 8” shallow and 2 metra adapters. Give it alittle time to break in and u get alittle more bass but cleaner. Or use the factory sub as a signal and throw in a beefer 8” and then amp it for more.
 

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Awesome Job! What is the outer dimension of your 8" sub? I have a JL 12TW3-D4 (12" extreme shallow mount) that I pulled from my Jeep (before I traded it in for my RAM) and it has an overall 13" outer dimension. I know it would fit depth wise as it only needs 3.5" max. I just don't know if the 13" outer diameter will fit in that space. The sub runs optimal at .5 to .8 cuft of airspace so I should be able to get that or close to it. I too would like to keep the fold flat floor. I'm dying to try it out but I won't get a chance just yet because I'm in Afghanistan until early March.
 
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Awesome Job! What is the outer dimension of your 8" sub? I have a JL 12TW3-D4 (12" extreme shallow mount) that I pulled from my Jeep (before I traded it in for my RAM) and it has an overall 13" outer dimension. I know it would fit depth wise as it only needs 3.5" max. I just don't know if the 13" outer diameter will fit in that space. The sub runs optimal at .5 to .8 cuft of airspace so I should be able to get that or close to it. I too would like to keep the fold flat floor. I'm dying to try it out but I won't get a chance just yet because I'm in Afghanistan until early March.

With the fold flat floor there is no way to make a 12” sub fit. 10” would be pushing it but when u step up the size you step up the airspace which there isn’t a lot of. You could delete the stock sub and gain space for a larger single but I still think a 12” shallow is too much. I ran a pioneer 12” shallow in my 14 and ran a amazon 12” box. I had to add 3/4” MDF to space the sub up bc like yours it’s actually 13” and wide. I then had shave the inside of the sub box bc it’s so wide. But I didn’t have the fold flat floor and I still had to put spacers on the rear seats. If your trying to keep the fold flat floor I wouldn’t go bigger than 8” due to air space limitations. 10” could work but you would be choking the sub out unless u make the box longer to increase air space.
 

17CrewCab1500

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That looks awesome! I wanted to do something like that myself before these trucks came with subs. I know these factory ones don't close to that, but works for me for now.

I've always wanted to try my hand at this fiberglass. Looks rather simple. But I know making it look simple comes with experience.. haha
 

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Curious which brand subwoofer box in the low end of the price range fits tightest in the crew cabs under the seat. Was considering buying one and cutting the top section off and fibreglassing a new top flush across the entire area much like the original poster, just across both sides. Thought once trimmed to the height i want I could fill it with water and measure it to see real volume and then cut rings and select subs based on the final numbers. I could just fibreglass a tub section in the truck and then finish it outside of the truck, but really what I want to do is fibreglass in the yard vs in the truck. I'd be adding fibreglass to attach the top so fit for most air volume is most important.
 
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Curious which brand subwoofer box in the low end of the price range fits tightest in the crew cabs under the seat. Was considering buying one and cutting the top section off and fiberglassing a new top flush across the entire area much like the original poster, just across both sides. Thought once trimmed to the height i want I could fill it with water and measure it to see real volume and then cut rings and select subs based on the final numbers. I could just fiberglass a tub section in the truck and then finish it outside of the truck, but really what I want to do is fiberglass in the yard vs in the truck. I'd be adding fiberglass to attach the top so fit for most air volume is most important.

My experience with prefabbed boxes (ran one in my 14CC) was that the top section (that sat above the lip in the floor) was at minimum 3". I can measure the prefab box as i still have it in my basement when i get home. The fitment of the bottom wood section only fits into the floor recess very crudely... basically looks like a funky misshaped bucket and leaves LOTS of space unused. This is why the fiberglass bottom is the best option as it wont be thicker than 1/8" and it will use EVERY bit of space available. So your gaining the unused space the prefabbed boxes don't even utilize and your gaining the thickness of the MDF they use 1/2, 5/8, 3/4".

Also the bottom "floor" of the prefab boxes is what sits ontop of the storage space lip... so you would have to take the box and cut the bottom bucket area off and then trim it lower as your sub top surface has to be lower than the top of the lip otherwise the fold flat floor will contact it... also the sub cone will protrude above its resting surface as its used so you have to give yourself added space.

Your better off starting from scratch as literally you would be junking 80% of the preffabed box and you would be getting all the required sqft for the sub (limiting yourself immensely). Just do one solid layer of glass in the truck, mix it heavy on the hardener and in 30min pull it out, then add extra layers on the inside when its out of the truck. The issue isn't going to be the smell of the glass when its in the truck setting... it will be that the box is going to smell for a while afterwards... like a few months lol. So unless you plan to leave it out of the truck for 2 months after finishing till it stops stinking then your going to get the smell either way.

The good news is my setup doesn't smell anymore and the sub and box have been working great! Ive actually had to turn down the LOC signal as it was pushing too hard and rattling things in the truck.
 

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My experience with prefabbed boxes (ran one in my 14CC) was that the top section (that sat above the lip in the floor) was at minimum 3". I can measure the prefab box as i still have it in my basement when i get home. The fitment of the bottom wood section only fits into the floor recess very crudely... basically looks like a funky misshaped bucket and leaves LOTS of space unused. This is why the fiberglass bottom is the best option as it wont be thicker than 1/8" and it will use EVERY bit of space available. So your gaining the unused space the prefabbed boxes don't even utilize and your gaining the thickness of the MDF they use 1/2, 5/8, 3/4".

Also the bottom "floor" of the prefab boxes is what sits ontop of the storage space lip... so you would have to take the box and cut the bottom bucket area off and then trim it lower as your sub top surface has to be lower than the top of the lip otherwise the fold flat floor will contact it... also the sub cone will protrude above its resting surface as its used so you have to give yourself added space.

Your better off starting from scratch as literally you would be junking 80% of the preffabed box and you would be getting all the required sqft for the sub (limiting yourself immensely). Just do one solid layer of glass in the truck, mix it heavy on the hardener and in 30min pull it out, then add extra layers on the inside when its out of the truck. The issue isn't going to be the smell of the glass when its in the truck setting... it will be that the box is going to smell for a while afterwards... like a few months lol. So unless you plan to leave it out of the truck for 2 months after finishing till it stops stinking then your going to get the smell either way.

The good news is my setup doesn't smell anymore and the sub and box have been working great! Ive actually had to turn down the LOC signal as it was pushing too hard and rattling things in the truck.
My factory sub rattled stuff as did potholes, rumble strips etc. so that's why my whole cab is covered in soundproofing now. I know I'd be cutting off a large chunk of box top. I'd only salvage the tub and the rest of the box would be trash. Just wondered if any of the prefabs actually had a tight fit in the tub. Would think at least 1 company would have a good mould to build out of. I can run my stealthbox until I finish the new box so it can sit around curing. If it comes down to it what you suggested is likely what I'll do, but if I can pick up something on the cheap and save me the in truck work I'd prefer it.
 
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My factory sub rattled stuff as did potholes, rumble strips etc. so that's why my whole cab is covered in soundproofing now. I know I'd be cutting off a large chunk of box top. I'd only salvage the tub and the rest of the box would be trash. Just wondered if any of the prefabs actually had a tight fit in the tub. Would think at least 1 company would have a good mould to build out of. I can run my stealthbox until I finish the new box so it can sit around curing. If it comes down to it what you suggested is likely what I'll do, but if I can pick up something on the cheap and save me the in truck work I'd prefer it.

The box I have was a decent fit, couldnt move (twist) it once it was pushed in but like I said the bucket area leaves alot of unused space (around the bucket and under the lip... ALOT) . My custom box I almost can't get it out it fits so tight and I know I'm using 100% of the space. i think I barely made the 1cuft of space needed for my 8" kicker sub.

I dont think any of the companies have that mold you want... they all try to use some of the space with the crude bucket designs but the space in that area is very fluid/organic looking with odd curves and shapes (you can see it in my pics with the blue tape) None of the boxes Ive seen use all of that space... instead they just build UP and add that space above the lip bc its easy and offers more space per inch than going down with something rigid like MDF. Good luck! I still feel like you will need to mold inside the truck if you go fiberglass.
 

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You may be right. I can easily get a finger around my jl box and can see right down to the bottom. If it was tight it could easily drop the top down flush and have plenty of airspace for the 10w1s I'm running and as a bonus I could pull the seat spacers out, have the load floor supported better and not have all that room for things to fall in there. Every time I look at it I get more annoyed so I want to change it for my own sanity.
 

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Wow, very clean setup, looks better than the OEM fit. With a box I bought on here homemade from a member, the box hasn't been the issue, it's getting good signal to Amp, tried off the factory sub and I just don't like sound quality. Bought better loc, still not satisfied, bought a ax-dsp, sounds fantastic since it sums front and rear channels so bass sounds excellent, but the ax dsp has software issues with Android, so right now using bass knob to control volume grrrrr.
 
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