Fox Upgrading the Fox Body factory Head Unit and Speakers

It's time to replace my 1987 Mustang's factory head unit and speakers. Can hardly see the head units display. To my surprise, I opened up my door panel speaker cover to find out - no speaker. Ha. I wanted to check the door panel speaker magnet to measure its depth so that I may replace this speaker with a speaker size that would not interfere with the function of the window up/down. So my car has the dash 3.5" speakers and the rear 6X8" speakers only. I want to replace the head unit and add an amp and I was planning on replacing dash/door and rear speakers. I'm sure I would be happy with decent speakers with about a 50 watt RMS rating. My Fox is a hatchback. For you guys/gals that have updated your approximately 30 plus year old factory stereo, what did you do? Did you add door speakers in addition to replacing the rear and dash speakers. Just replace and upgrade the current rears and dash speakers and call it done? Or did you just add door 6.5" and replace rears and call it done? It seems the dash 3.5" speakers aren't very common anymore. I didn't remove my door panel, for the Fox Mustangs that did not get the factory door speakers, would you know if the factory speaker wire is still run into the doors that could be used when installing door speakers or do you have to run your own speaker wires into the door panels? Thanks.
 
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if you actually care about fidelity, the factory wiring is crap. The old assed factory wires in the car have oxidized to the point of no longer being able to adequately move the current to the speakers. Most aftermarket installs will replace the factory 20ga. wire with 18 ga. The 3.5 speakers have never been worth a crap IMO, and are at best marginal even when replacing them w/ aftermarket units. I have 6.5” component speakers in front, and tweeters replace the 3.5” factory units. Factory 6.8’s are odd balls too, and the best pieces to replace them with that actually fit are just warmed over stockers. 6x9’s are the typical premium aftermarket replacements, but probably won’t fit, or will require some creativity to make them fit.
 
The stock head unit has a bulb for the display. Yours is likely burned out. Mustangs with the premium stereo setup got 6 speakers and an amp behind the original radio. The base model radio lacks the amp and door speakers. Sounds like that’s what you have.


I would start from scratch. Do not reuse any of the old wiring it’s not worth it.

Also, list your stock stuff on eBay. You’ll be surprised what you get for it.
 
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I did a Kenwood Bluetooth only head unit, soundtream 4 ch amp (75w/ch), infinity 6.5 in doors and silk dome tweeters up-front, 6.5 infinity in the rear. Door/tweeters are components and have a crossovers, rear ive adjusted at the amp. Plenty of volume, have a powered 10" Fosgate sealed sub in the trunk (mine is a vert). Pretty happy with quality and volume. Good luck.
 
The stock head unit has a bulb for the display. Yours is likely burned out. Mustangs with the premium stereo setup got 6 speakers and an amp behind the original radio. The base model radio lacks the amp and door speakers. Sounds like that’s what you have.


I would start from scratch. Do not reuse any of the old wiring it’s not worth it.

Also, list your stock stuff on eBay. You’ll be surprised what you get for it.
I called the Ford Dealership to see if they could tell me what the factory amp size dimensions would be as my 87LX does not have the factory amp. The dealership checked and apparently have no information they can find regarding factory amp dimensions. Would any of you guys know what the factory amp dimensions would be? I found a nice 85W X 4ch at 4 ohm class D amp on sale and wondered if this amps dimensions of 8.46" X 7.48" X 1.97" would fit in where the factory amp would go in console behind current factory head unit.
 
I called the Ford Dealership to see if they could tell me what the factory amp size dimensions would be as my 87LX does not have the factory amp. The dealership checked and apparently have no information they can find regarding factory amp dimensions. Would any of you guys know what the factory amp dimensions would be? I found a nice 85W X 4ch at 4 ohm class D amp on sale and wondered if this amps dimensions of 8.46" X 7.48" X 1.97" would fit in where the factory amp would go in console behind current factory head unit.

This is the factory 87-92 amp that sits behind the radio. It bolts to the bracket that bolts to the trans tunnel. The outer bracket bolts up to the two circles you see on the transmission hump bracket. You can measure that bracket and assume the dimensions of the amp from that and referincing this pic

1638197747399.png


I haven't had one in my hands in some time, but if i had to guess it's 6" x 4" x 1.5" give or take.
 
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This is the factory 87-92 amp that sits behind the radio. It bolts to the bracket that bolts to the trans tunnel. The outer bracket bolts up to the two circles you see on the transmission hump bracket. You can measure that bracket and assume the dimensions of the amp from that and referincing this pic

1638197747399.png


I haven't had one in my hands in some time, but if i had to guess it's 6" x 4" x 1.5" give or take.
Thank you very much for your reply. How amp appearances change over 34 years eh? Wouldn't even of guessed that was an amp picture. I guess without actually removing my current head its still tough to really know what size new amp could physically go into the location of where the factory amp was? I was hoping to take advantage of some black Friday sales and purchase the amp before installing the whole new audio system when our weather here warms back up near spring. The other amp I was considering was 8.75" wide X 1.99" Height and 5.59" depth. Thanks again for taking the time to reply.
 
Mounting the amp under the passenger seat is a commonly done thing. in 1993, Ford mounted the revised amp there.

Here's my 93 OEM amp under the pass seat. This one is a little bigger at 7-8" x 5-6" x 2"

1638203830028.png
 
Mounting the amp under the passenger seat is a commonly done thing. in 1993, Ford mounted the revised amp there.

Here's my 93 OEM amp under the pass seat. This one is a little bigger at 7-8" x 5-6" x 2"

1638203830028.png
Makes me wonder now if best practice would simply to be to forget about trying to find an amp that does fit where the factory one did for my model 87 year and just look to install the new amp under passenger front seat? If installing amp under the seat would you think the process for wiring amp to the speakers and head unit would be more time consuming as compared to amp mounted in factory location for 1987 models?
 
Not really. Biggest issue is getting power to the unit. You can ground to the floor pan there. The other wires run like this in the 1993. You can take a similar routing under the carpet.

1638216492060.png
 
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I have an Alpine head unit in mine with the 4x45w RMS power pack amplifier add on. It operates "inline" with the wiring via Alpine harness that plugs into the back of the head unit and into the factory wiring. It powers a pair of 5.25" components with the tweeters located in the dash in place of the 3.5" factory speakers and 6x8"s in the rear. Here's a picture of the amp and passive crossovers mounted on starboard and installed under the passenger seat.

I admire the guys restoring and keeping the factory radios/amps but I need my tunes loud and clear when I'm cruising.
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I often have wondered if messing with the stock stereo in a foxbody is worth it with stock speaker locations.
I've had sub boxes, bass tubes etc. and i have found that does the job (i have none of this now) but in all stock locations, can a stereo really sound good in a high mileage fox with a loud exhaust?
I cut up my stock wiring when i was a kid, kinda wish i didn't.
 
can a stereo really sound good in a high mileage fox with a loud exhaust?

That's just it though. When i cruise around in my fox, i listen to the exhaust. That's all i want to hear. The few times I've played music, i've lowered the volume down so i can clearly hear the exhaust note. 99% of the time, the radio is off. As much as i've toyed around with the idea of a Double din touchscreen with modern features, it likely would stay off or muted. So i might as well restore the OEM stereo (or in my case a 93 CD player)

My daily drivers, different story. Automatic trans, nice and quiet on the highway, i blast the tunes. I like a nice stereo, but these days the infotainment center is so integrated that it's difficult to modify a modern system.


Certainly no knock against those who want good tunes in their Foxbody. I've had some buddies put together some loud systems back in the day. It was just never my thing
 
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That's just it though. When i cruise around in my fox, i listen to the exhaust. That's all i want to hear. The few times I've played music, i've lowered the volume down so i can clearly hear the exhaust note. 99% of the time, the radio is off. As much as i've toyed around with the idea of a Double din touchscreen with modern features, it likely would stay off or muted. So i might as well restore the OEM stereo (or in my case a 93 CD player)

My daily drivers, different story. Automatic trans, nice and quiet on the highway, i blast the tunes. I like a nice stereo, but these days the infotainment center is so integrated that it's difficult to modify a modern system.


Certainly no knock against those who want good tunes in their Foxbody. I've had some buddies put together some loud systems back in the day. It was just never my thing
At least you listen to the exhaust, i listen to every creak and rattle, they all drive me nuts.

Still begs the question, can a quality stereo system be done in foxbody using only stock locations? Amps or no amps, i just don't think the car was ever designed to have any type of quality sound. Now if you send all the mids and highs to the factory location speakers then use a subwoofer, that works.
 
Funny how you refer to listening to the exhaust. That's what I do most of the time. When I was a kid I had a F-150 with 302, and strait pipes coming strait up from the bed. There is no better sound than the 302. The other day a 69 Camaro came flying bye me, and it sounded like a dog. A stereo in my car would have to be very loud to cover up my American Thunder, and I'm two layered sound proofing
 
At least you listen to the exhaust, i listen to every creak and rattle, they all drive me nuts.

Still begs the question, can a quality stereo system be done in foxbody using only stock locations? Amps or no amps, i just don't think the car was ever designed to have any type of quality sound. Now if you send all the mids and highs to the factory location speakers then use a subwoofer, that works.
Yes it can. Component set for the front stage. Tweeters in the dash in place of the 3.5”. Make sure they are on a gimbal mount that allows aiming. 6.5” or 5.25” in the doors. Add some power a little sound processing throw in some time alignment and a 10” sub with 200-300W and you would be shocked at how good it can sound. I like silk dome tweeters BTW for their smoothness.

My exhaust sounds dang to too, but I still love my tunes.
 
Yes it can. Component set for the front stage. Tweeters in the dash in place of the 3.5”. Make sure they are on a gimbal mount that allows aiming. 6.5” or 5.25” in the doors. Add some power a little sound processing throw in some time alignment and a 10” sub with 200-300W and you would be shocked at how good it can sound. I like silk dome tweeters BTW for their smoothness.

My exhaust sounds dang to too, but I still love my tunes.
What i'm getting at is stock locations only. No Sub.
I feel like sub woofers never look right in a foxbody or block access to the spare tire.
 
At least you listen to the exhaust, i listen to every creak and rattle, they all drive me nuts.

I listen to that too.

I mean it's amazing how far modern vehicle chassis engineering has come. My DD has more miles than my fox (130k vs 100k), and i can drive around on a bumpy road and really not hear a thing other than muffled thumps from the wheel wells.

I get in my fox and realize what a flimsy rattle-can it is even with additional chassis bracing.
 
What i'm getting at is stock locations only. No Sub.
I feel like sub woofers never look right in a foxbody or block access to the spare tire.
Here's my little 10" with the amp mounted to the sub box. To access the spare tire you just lay the seat down, unclip the hold down strap, and roll it forward. Now the 2 12"s I had in my high school years were a different story.

The sub isn't required if you don't mind less bass. A good set of components in the front and 6x8"s in the rear can should good when driven with clean power.

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