anyone mounted an amp to a trunk lid?
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=110086
Printed Date: May 13, 2024 at 6:56 PM
Topic: anyone mounted an amp to a trunk lid?
Posted By: bigjohnny
Subject: anyone mounted an amp to a trunk lid?
Date Posted: December 27, 2008 at 3:40 PM
I know its not recommended to mount amps to your trunk lid, for many reason, but what if its your only option?
Ive been searching around all day looking for info about mounting amps to trunk lids, and others projects to get some ideas, but Ive found literally nothing on the subject.
Has anyone done this with any success? Does anyone have any good links about it?
I work with alot of materials at work that are very rubbery, and excellent for shock absorption (I make orthotics) so finding a material to dampen shock and vibration shouldn't be an issue.
Ive also been considering using Peltiers for a cooling solution either directly mounted to the amp, or mounted to heatsink/fans that could blow cool air around inside the fiberglass cover i'd like to build.
Replies:
Posted By: soundnsecurity
Date Posted: December 28, 2008 at 3:14 PM
just make sure it's ventilated and that your wires cant get pinched in the hinges in any way. also it will make your trunk lid pretty heavy so you might want to mount a strong air piston to take some of the weight and so that your trunk will pop correctly when you push the button
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Posted By: bigjohnny
Date Posted: December 28, 2008 at 6:10 PM
Ive been considering the weight, I might have to stiffen the springs, or Ive been considering just taking the springs out and using something like hood lifts.
Another thing ive been toying with is putting them or one of them, on the roof of my interior at the back. I dont think it would obstruct my view, and im fairly certain it could be done.
Im just not sure what i'd use as a crossmember, or how id get it all installed.
Posted By: paidnfull
Date Posted: December 29, 2008 at 4:07 PM
All I have to say is Heat Rises
Posted By: bigjohnny
Date Posted: December 30, 2008 at 7:15 AM
ya, I didn't overlook that, but my trunk lid is my only real option for mounting my amps.
Obviously im going to have to ventilate them well, but the heat might still be an issue even if i mounted them to the bottom because its all contained.
Posted By: soundnsecurity
Date Posted: December 30, 2008 at 10:30 PM
just dont mount it flush with the surface of the trunk so that it can get airflow all around the amp
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Posted By: bigjohnny
Date Posted: December 31, 2008 at 7:05 AM
what i was considering doing is making a fiberglass cover for it, and inside/underneath the cover have a couple of high powered peltiers mounted to heat sinks to blow cool air around inside the cover, and vent it out into the trunk.
Im not sure how well it would work because ive already burned out two 2a power supplies testing, and couldnt get the heatsink i had very cold, but they also require more amperage to work properly.
they do it with portable coolers, my parents have one that keeps stuff hot or cold.... they just plug it into the lighter and reverse the peltier accordingly.
Posted By: DYohn
Date Posted: December 31, 2008 at 10:22 AM
Pertiers are not a good idea. It you need to provide cooling, use fans. And don't mount your amps upside down, even with fans. ------------- Support the12volt.com
Posted By: bigjohnny
Date Posted: December 31, 2008 at 6:28 PM
why are they a bad idea other than the amount of current they draw, and why not mount the amps upside down?
I would like to still be able to see them, if i hang them from a rack, then they wont be visible.
could i mount them to the roof on the interior of my car? Im already planning on putting in a crossmember and installing an overhead console.
Posted By: DYohn
Date Posted: December 31, 2008 at 6:57 PM
bigjohnny wrote:
why are they a bad idea other than the amount of current they draw, and why not mount the amps upside down?
I would like to still be able to see them, if i hang them from a rack, then they wont be visible.
could i mount them to the roof on the interior of my car? Im already planning on putting in a crossmember and installing an overhead console.
Peltier's are a bad idea because they are very inefficient and they need to be mounted directly to the cooling target. Plus, you'll probably still need a fan to remove the heat from the Peltier devices. Mounting most amps upside down will void the warranty as it destroys the designed colling air flow. Upside down mounting is usually a recipe for very short life span. You can mount them anywhere you like, just don't do it upside down.  ------------- Support the12volt.com
Posted By: ckeeler
Date Posted: December 31, 2008 at 7:21 PM
ive mounted tons of amps upside down and never had a problem. never had a customer complaint of thermal shutdown either. (of course i never did it with a cheap amp either). i never did it on a trunk lid though. i always mounted them under the rear decks of cars, in the center in between the rear speakers and just used spacers to space them out from the bottom of the rear deck so that there was some room for air flow. you wont have to mess with the trunk lid springs or adding shocks or any of that other stuff. and how many factory amps have you seen mounted there where i just described? ive seen quite a few myself.
Posted By: i am an idiot
Date Posted: December 31, 2008 at 7:49 PM
Mounting any amplifier "right side up" is really mounting the amp upside down. With the bottom of the amp mounted to the floor of the vehicle, the components mounted to the circuit board are dangling and have to deal with the force of gravity all day long. When the manufacturers say not to mount it upside down, they are telling you to not have the heat sink mounted to a surface that will prevent air from getting to the heat sink. That would be bad. Mounting them upside down with the bottom cover against the mounting surface is fine. Upside down with the heat sink flat against the mounting surface, not so fine.
Posted By: bigjohnny
Date Posted: January 01, 2009 at 9:25 AM
ok, couple of things here. first off, ckeeler, if I mount it to my trunk lid, I will have to get stiffer springs or shocks or something, because my trunk as it is, already has trouble staying open. Ive already had it fall on my head a couple of times because of a mild breeze (somebody must have sneezed 20' away ;)).
Mounting two amps to my lid will definitely prevent it from staying open.
Peltiers..... Not arguing with anything here, I see what your saying about them, but how does it work in the thermoelectric coolers then?
As I mentioned my parents have an electric cooler that uses a peltier to heat or chill a heatsink, and a fan simply blows the hot or cold air around.
Now I do realize that all its doing is blowing cool air around in a small space, with no extra heat generated to counteract the cold, and as such the cold air, helps to further cool the peltier.
In the trunk it would be entirely different.
another thought is to put fans in my rear deck, to vent the trunk air into the cab, or at the very least, to simply put vents in my rear deck to allow the hot air from the trunk to vent into the cab, and cool air to get into the trunk.
All I would need to do for that is to cut holes in my rear deck fabric.... the holes are already there in the metal.
Now, the upside down mounting issue; For now i've got an Insignia 600W amp (NS-P200 kit) as well as a Dual 150W RMS 4/3/2ch amp (XPA4100).
I've looked inside the Dual amp, and its components are mounted to the bottom, facing up, so if it was upside down the stuff inside would be upside down also. I don't know about the insignia amp, but its probably the same.
I wouldn't have it mounted upside down so its really upside down, IE the top of the amp physically touching anything..... it would be hanging. So I get whats being said about that..... would seem pretty foolish to just flip it over and mount it upside down lol.
Im also thinking about maybe putting a channel in my fiberglass cover that will connect to the rear deck to pull the amps cooling air from the cab.
a temp. gauge is also another consideration to keep an eye on trunk and amp temps.
Its alot of planning, but ive got all winter to figure it out. There isnt much i can do in the snow :)
Posted By: i am an idiot
Date Posted: January 01, 2009 at 9:39 AM
If the trunk uses gas springs to hold it up, if you replace them they will fail again. i discovered a fix for them when I got in an accident. My gas springs were shot, I was hit in the side of the car, my sub enclosure hit the left spring and bent it, when the rear wheels of my car wound up in the ditch, the sudden decelaration slid the box and bent the other gas spring. Upon opening my rear hatch, the bend in the shaft offered some extra resistance that actually held the hatch open. So if you do have gas springs, open your trunk and pull the springs inward to put a slight bend in the shaft. Not so much that you have trouble closing it but enough that it will stay up when extended.
Posted By: DYohn
Date Posted: January 01, 2009 at 9:53 AM
Hey I've given you my advice, but you do what you want. Be sure to tell us how it all works out. You'll need at least 15 amp power supply for each Peltier you try to use. ------------- Support the12volt.com
Posted By: ckeeler
Date Posted: January 01, 2009 at 12:50 PM
bigjohnny wrote:
ok, couple of things here. first off, ckeeler, if I mount it to my trunk lid, I will have to get stiffer springs or shocks or something, because my trunk as it is, already has trouble staying open. Ive already had it fall on my head a couple of times because of a mild breeze (somebody must have sneezed 20' away ;)).
Mounting two amps to my lid will definitely prevent it from staying open.
i said ive never mounted one to a trunk lid, and i dont recomment it either. i was recommending under the rear deck in between the 2 rear speakers (if you have any there).
Posted By: ckeeler
Date Posted: January 01, 2009 at 12:56 PM
i am an idiot wrote:
If the trunk uses gas springs to hold it up, if you replace them they will fail again. i discovered a fix for them when I got in an accident. My gas springs were shot, I was hit in the side of the car, my sub enclosure hit the left spring and bent it, when the rear wheels of my car wound up in the ditch, the sudden decelaration slid the box and bent the other gas spring. Upon opening my rear hatch, the bend in the shaft offered some extra resistance that actually held the hatch open. So if you do have gas springs, open your trunk and pull the springs inward to put a slight bend in the shaft. Not so much that you have trouble closing it but enough that it will stay up when extended.
if you go to a good parts store (not an autodork or a checkoff) a good parts man can look up your vehicle to see the part number off the lift support shocks your car has, then he can proceed to take out a book (yes folks, good parts people use books and not just push buttons on a keyboard to look up parts) and find that part number and see its dimentions and weight rating, then, use that same catalog to find another shock with the same dimentions and mounting ends with a different weight rating, almost any that you want. what an idea huh??
Posted By: bigjohnny
Date Posted: January 01, 2009 at 6:09 PM
ckeeler: I thought you mentioned something about not needing to replace my lid supports.... must have gotten confused with i am an idiot.
Anyway, I dont have enough room width wise to mount my amps to the rear deck, its pretty small. also the speaker boxes will be sitting directly under it, which leaves only 1" space above the boxes.
i am an idiot: About the springs, I can open the book and check for myself which springs it uses, I have the dealership service manual for my car. But it doesnt use gas shocks.... its got some kind of weird rod that goes across the rear deck to each lid mount. It isnt very strong and I'd like to replace it/them anyway.
DYohn: I wasn't trying to contest anything stated, so i hope i wasnt taken that way, I'm simply looking for more infomation. I'm not set on using pelts, like i said, i'm really just trying to plan/research and gather as much info about my whole project as I can.
Pelts probably arent the best solution, but id probably still install a couple of thermal probes to monitor temps.
I have been considering a pelt to use as a form of heater to warm the trunk in the winter so i dont have to run my speakers cold.
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