Installation of an aftermarket subwoofer system in a 1966 Chevrolet Corvette, including removal of trunk access panels, wiring routing from head unit, amplifier mounting, and enclosure installation.

Warnings

Tools required

Parts

• Subwoofer speaker × 1 — Match to enclosure size and power handling
• Subwoofer enclosure × 1 — Corvette-specific or custom-fit design
• Amplifier × 1 — Match RMS wattage to subwoofer specification
• Amplifier wiring kit × 1 — Minimum 8 AWG for typical application
• RCA interconnect cables × 1 — Shielded twisted pair, length as needed
• Speaker wire × 1 — 12-16 AWG, length as needed
• In-line fuse holder with fuse × 1 — Match amplifier power requirements
• Butt connectors and ring terminals × 1 — Assorted sizes
• Wire ties × 20 — UV-resistant nylon

Preparation

1. Park vehicle on level surface and engage parking brake.
2. Disconnect negative battery cable and secure away from battery terminal.
3. Remove luggage from trunk area and clean workspace.
4. Plan wire routing from head unit location through firewall or along rocker panels to trunk.
5. Verify amplifier and subwoofer specifications match and calculate total power requirements.
6. Test fit subwoofer enclosure in trunk to determine optimal mounting location without interfering with spare tire or structural members.

Procedure

1. 1

   Remove trunk access panels and prepare mounting location
   Access the rear storage/luggage area behind the seats. The 1966 Corvette (C2) does not have a conventional exterior trunk; luggage is accessed from inside the cabin behind the seats. Remove any rear interior trim or carpeted panels as needed to access fiberglass mounting surfaces. Remove 8 screws from each side panel and carefully pull panels away from spring clips. Inspect fiberglass structure for suitable amplifier and enclosure mounting locations that do not interfere with the rear storage area access or rear window/hatch.
2. 2

   Route power cable from battery to trunk
   Run the amplifier power cable from the battery positive terminal through an existing firewall grommet or along the rocker panel beneath the door sills. In the 1966 Corvette, route the cable through the passenger side rocker panel by removing the door sill trim plate (secured with 4 screws). Install the in-line fuse holder within 18 inches of the battery connection but do not install the fuse yet. Secure cable with wire ties every 12 inches, keeping it away from sharp edges and moving parts.
3. 3

   Route RCA and remote turn-on cables
   Run shielded RCA interconnect cables and remote amplifier turn-on wire from the head unit location to the trunk. Route these signal cables along the opposite side of the vehicle from the power cable to minimize electrical noise. In the 1966 Corvette, the most direct path is through the passenger side kick panel area and along the rocker panel. Use wire loom to protect cables and secure with wire ties.
4. 4

   Establish ground connection in trunk
   Identify a suitable grounding point on bare metal in the trunk area. Remove paint, rust, or undercoating from a 2-inch diameter area using sandpaper or wire brush to expose clean bare metal. The rear trunk floor support structure provides the best ground. Attach the amplifier ground wire using a ring terminal and self-tapping screw or existing bolt. Verify continuity between ground point and battery negative terminal using multimeter (should read less than 0.5 ohms).
5. 5

   Mount amplifier
   Mount the amplifier to the trunk side panel or floor using the amplifier mounting brackets. In the 1966 Corvette fiberglass body, use a backing plate (aluminum or plywood) behind mounting screws to distribute load and prevent cracking. Mount amplifier with heat sink fins oriented for maximum airflow and controls accessible. Typical mounting requires 4 screws through amplifier chassis. Ensure amplifier location allows adequate ventilation and does not contact any metal that could cause grounding issues.
6. 6

   Connect power, ground, and remote wiring to amplifier
   Connect the power cable to the amplifier positive terminal, ground cable to amplifier ground terminal, and remote turn-on wire to amplifier remote terminal. Strip wire ends 0.5 inches and use ring terminals for power and ground connections. Tighten amplifier terminal set screws securely. Route excess wire length neatly and secure with wire ties. Double-check that no bare wire is exposed and all connections are tight.
7. 7

   Connect RCA signal cables to amplifier
   Connect the RCA interconnect cables from the head unit to the amplifier input jacks. Ensure left and right channels are correctly matched. Route RCA cables away from power cables and secure with wire ties. If amplifier has gain controls, set them to minimum position initially for later adjustment.
8. 8

   Install and wire subwoofer in enclosure
   If subwoofer is not pre-installed in enclosure, mount subwoofer to enclosure using the mounting screws provided with the speaker (typically 8 screws). Observe correct polarity marking on subwoofer terminals. Connect speaker wire to subwoofer terminals, ensuring positive to positive and negative to negative. Route wire through enclosure terminal cup if provided, or through a drilled hole with grommet protection.
9. 9

   Position and secure subwoofer enclosure
   Position the subwoofer enclosure in the planned trunk location. In the 1966 Corvette, typical placement is in the rear storage area behind the seats or along one side. Secure enclosure using L-brackets, straps, or Velcro to prevent movement during driving. Verify the enclosure does not rattle or contact body panels and does not obstruct rear visibility or cabin access.
10. 10

    Connect speaker wire from amplifier to subwoofer
    Run speaker wire from amplifier speaker outputs to subwoofer terminals. Use 12-16 AWG wire appropriate for the run length and power level. Maintain correct polarity throughout (mark positive wire with tape if needed). Strip wire ends 0.5 inches and connect to amplifier speaker terminals and subwoofer terminals. If amplifier is bridged for mono operation, follow amplifier manual for correct terminal configuration. Tighten all terminal connections securely.
11. 11

    Complete battery connections
    At the battery, attach the power cable ring terminal to the positive battery post using the battery post bolt. Ensure the in-line fuse holder is still empty (no fuse installed). Reconnect the negative battery cable to the battery. This allows testing of all connections before energizing the amplifier circuit.
12. 12

    Initial system test and amplifier adjustment
    Turn ignition to accessory position and turn on head unit. Insert the fuse into the in-line fuse holder to energize the amplifier. Check amplifier LED power indicator illuminates. Play audio source with bass content at moderate volume and verify subwoofer produces sound. Adjust amplifier gain control by increasing from minimum until subwoofer output matches front speakers at normal listening level. Set low-pass crossover frequency to 80-100 Hz as starting point. Listen for distortion and reduce gain if present.

Reassembly

1. Reinstall all trunk panels and secure with original screws and clips.
2. Reinstall door sill trim plates along rocker panels where removed.
3. Verify all wire connections are secure and no wires are pinched by panels.
4. Check that trunk lid opens and closes freely without contacting subwoofer enclosure.
5. Secure all loose wiring with additional wire ties as needed.

Verification

• With engine running, verify voltage at amplifier power terminal reads 13.5-14.5 volts (generator charging).
• Play test tracks with deep bass content and verify subwoofer produces clean, undistorted output.
• Check for rattles or vibrations from enclosure, amplifier mounting, or trunk panels at various volume levels.
• Verify amplifier does not overheat during extended use (heat sink should be warm but touchable).
• Test remote turn-on function by turning head unit off and verifying amplifier powers down (LED off).
• Inspect all electrical connections for security and proper insulation.
• Confirm no interference with AM/FM radio reception or other vehicle electrical systems.

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