You’ve seen how our AMD ’67 Chevelle has transformed from a worn-out eyesore into an eye-catching and tire-melting SS396 once again. Now it’s time to upgrade one area on this A-body that’s seen big technological changes since the days when Chevrolet cranked out Chevelles by the minute: the sound system inside the cabin.
Back in ’67, Chevelle buyers didn’t have many factory-installed options for their on-board listening pleasure. There was the RPO U63 push-button AM radio or the RPO U69 AM/FM mono radio, both with a single dash-mounted speaker, plus the RPO U80 auxiliary (rear shelf) speaker and RPO U57 tape player (8-track) that were available with either radio…or you could choose radio delete, for nonstop road noise and engine sounds.
Aftermarket choices were equally as limited back then, too. The era of in-dash radio/tape player combos and cassette tape drives had yet to arrive, so your choices involved underdash-mounted 8-track players, plus speakers whose technology—and construction—wasn’t too far removed from that of the kazoo.
Visually, our AMD Chevelle went from something dragged out of a field to a concours-appearing muscle car, but one thing it lacked was a radio. As sweet as our rebuilt Rat sounded, it is hard to rock on down the highway without any rock ’n’ roll. We wanted a modern sound system that would easily install in our SS396. Custom Autosound came through with its USA 630 II head unit (AM/FM stereo tuner, a “System 1” subwoofer and tweeters, a pair of kick panel–mounted speakers for the front, and a pair of 6x9 speakers for the rear shelf.
Installing it all was straightforward, though there is metal cutting needed to install the 6x9s in the rear shelf, just as there was back in the day when the first aftermarket stereo installers got to work.
We now have a sound system that’s up to the task of keeping our SS396’s driver and passengers supplied with tuneage they can not only hear over the 396, but feel—thanks to the powered subwoofer. But it doesn’t give off that thudbuzzthudthudbuzzbuzzthudbuzz that too many rides with subwoofer-equipped sound systems give off.
Take a look at what went in to our SS396’s dash, kick panels, trunk, and rear shelf, courtesy of Custom Auto- sound. (Installation was done by Darrell Kunda, shop manager of our Tampa Tech Center.)
1. Looks factory stock, doesn’t it? That’s the idea—until you turn on the power. Then, what looks like a stock AM radio dial is replaced by a modern LCD display.
2. First things first: With the stock radio relegated to history, installing the new one begins by removing the big chrome radio bezel from the dash.
3. Trial-fit the new head unit before attaching any mounting screws. It should be a snug fit, to prevent rattles and squeaks from showing up later on.
4. Next, install shims/spacers on the head unit’s control shafts and install the provided lock washers on the control shafts. That secures the head unit to the dash. Then install the knobs on the shafts.
5. The head unit is installed, so we’ll leave the power/speaker/antenna wiring below the dash for now and await the speakers/subwoofer installation.
6. Time to add the front kick panel speakers. Start by removing the step plates from each front doorway. That not only makes it easier to remove the carpets (for your later rear-speaker installation), but also exposes this pressed-in “channel” atop the rocker panel on each side, where we’ll route the rear speaker and subwoofer wiring later.
7. Remove the vent covers on the right kick panel—you’ll reuse the right-side one. Once that’s done, remove the OEM/existing kick panels.
8. Install the new Custom Autosound right-side kick panel, which has the front speaker already in place. (Don’t forget to reinstall the vent door on the right-side panel!) The fit here will also be a tight one, which will prevent any later squeaks and rattles.
9. Plug the kick panel speaker into the head unit’s right-front speaker input, per Custom Autosound’s directions. Repeat the installation on the left side, though you’ll likely have to remove the parking brake pedal assembly and move it aside so you can get at the left kick panel.
10. The tweeters are interesting because they resemble ’60s-era A/C vents. Start their installation by drilling two holes for the 1⁄8-inch self-tapping screws that will hold its mounting bracket in place. (We started with the right side here.)
11. Next, screw the tweeter into the mounting bracket, then tap the tweeter wire into the kick panel speaker wire. Once the right side’s done, repeat these steps (drill, mount, tap) to install the left-side tweeter.
12. We first wanted to install our subwoofer under the rear seat, but locating it in the trunk made more sense—especially when it comes to dissipating the heat it’s bound to generate once it’s cranking out the bass. Drill holes in the trunk floor for the 3⁄8-inch spacers at each corner and install the subwoofer.
13. Installing the rear speakers will be the toughest part of this job because of the cutting required. (Dual rear-speaker openings weren’t stamped into GM A-body rear shelves until 1973.) Also, you can see why it’s a good idea to remove the whole back seat—not just to access the rear shelf, but also to run the air hoses/power cords for the cutting tools you’ll need to use.
14. For the rear speaker installation, start by trial-locating the speaker grilles on the rear shelf and marking their centerlines and screw-hole locations on the shelf.
15. Next, use a rear speaker to cut a cardboard template, which you’ll need to cut out (and drill) the holes in the shelf.
16. We found the best way to cut the shelf is from underneath, given the tight confines under the back window.
17. When you get about halfway through your cut, you’ll need to clamp the metal that’s being cut so it doesn’t wiggle while you’re finishing the cut—and possibly break your saw blade.
18. Next, using your speaker grille, mark holes for the mounting screws and drill them. We drilled ours from underneath, with the speaker held in place, thanks to the lack of room between the shelf and rear window. Attach the speakers using the mounting screws provided for a trial fit.
19. Now it’s time to cut the shelf top for the speakers and their grilles. Remove the speakers and then put the shelf top in place. From underneath, trace along the speaker holes.
20. Remove the shelf top and put it on your workbench upside down so the speaker-hole tracings appear. Make your first cut through the foam underside along the marked cuts, leaving the board in the middle—and the vinyl on the top—untouched for now. Next, clean up the cut you made through the foam layer.
21. Drill a pilot hole in the center of the hole and use that hole to cut the board and vinyl with your pneumatic saw. Once that hole is complete, clean up the edges and reinstall the shelf top on the shelf. Using your template, drill the attaching-screw holes through the shelf top.
22. With all holes drilled and cleaned up, attach the speakers and grilles using the supplied hardware, per Custom Autosound’s instructions.
23. Here’s the Custom Autosound system’s head unit and tweeters installed, looking more like original options than aftermarket add-ons.
24. The subwoofer’s power controller went inside the factory ashtray.
25. There’s plenty of room in the SS396’s trunk for the subwoofer to breathe—and for it to create a killer bass line.
26. The Custom Autosound 6x9s look like they went in on the assembly line, with a sound that Delco’s R&D engineers could only dream of back then!
|Head unit: Custom Autosound USA 630 II: (fits the stock ’67 Chevelle dash without cutting)|
|AM/FM Stereo RDS tuner shows station/song/artist on LCD display|
|300 watts peak power|
|USB port for flash drive MP3/WMA playback|
|iPod dock and control (control your iPod from the buttons on the radio)|
|Direct 6 CD changer control|
|Negative LCD display (black background with white letters/numbers)—display looks like an old-school analog radio, until you turn it on|
|Alphanumeric display for MP3/WMA/iPod files|
|Electronic tuning and volume control|
|Two-channel RCA auxiliary input for satellite radio services, etc. (cable included)|
|12 presets (12 FM, 4 AM) with large, factory-style pushbuttons|
|Four-channel RCA preouts|
|Separate bass and treble|
|Power antenna lead|
|Manufacturer’s suggested list price (MSRP) for USA 630 II: $239|
|Front tweeters/subwoofer: Custom Autosound System 1 (Subwoofer and two tweeters)|
|Flat active aluminum subwoofer enclosure with 8-inch woofer, plus two-channel amplifier|
|Two 3-inch mid-tweeter/satellite speakers in die-cast metal housings (styled to look like ’67 Chevelle OEM underdash A/C outlets)|
|Remote bass level control|
|Amplifier installation kit included|
|Amplifier power: 150 watt subwoofer/2x50 watt mid/tweeter|
|Can be hooked up to any radio with speaker level or RCA inputs|
|MSRP for system 1: $299|
|Front tweeters/subwoofer: Custom Autosound System 1 (Subwoofer and two tweeters)|
|Kick panel speakers: Custom Autosound CAM 4X6 80 watt speakers|
|Factory-replacement kick panels with integrated 4x6-inch speakers that can handle 80 watts MSRP: $119/pair|
|Rear deck speakers: Custom Autosound CAM-693C 6x9 speakers|
|200-watt three-way 6x9 speakers|
|With factory-style flat metal grilles to maintain the original look|