Picture This: Two stunning big-block Chevelles parked side by side, identical in power. One has the standard SS hood, and the other boasts a cowl induction system. While the system adds no measurable horsepower, it offers something even cooler: a dramatic flap that opens under full throttle, sending a clear signal—this car is serious business!
If you think that's cool, you'll love how easy it is to install this system on your 1970-72 Chevelle or El Camino. Whether your car originally came with cowl induction or not, we’ll guide you through the entire installation process.
What You’ll Need:
All components are included in Eckler's Chevelles 1970-1972 Cowl Induction System (Part #606556):
- Cowl induction hood (if needed)
- Cowl induction door assembly
- Hood screen
- Air cleaner spacer
- Cowl induction air cleaner assembly
- AC intake relay and wingnut
- Vacuum actuator and support
- Cowl induction wiring harness and firewall grommet
- Valve frame kit
- Air control switch and bracket
- Flow control valve
Tip:
Whether you’re using your existing cowl hood or a new one, it’s best to remove the hood and place it upside down on a firm, level surface. While it’s possible to install the system with the hood attached, removing it makes the process much easier.
Compatibility:
A cowl induction system can be installed on any 1970-72 Chevelle equipped with a four-barrel carburetor, including the following engines:
Installation Steps
1. Prepare the Hood
- Remove the hood from your vehicle and place it upside down on a stable surface.
- Paint the cowl door and screen to match the body color.
- Be cautious when working around the hood’s sharp, stamped sheet metal edges.
2. Install the Valve Frame and Solenoid
- Insert the valve frame cage flap into the valve frame cage and secure it with the supplied retaining clips.
- Attach the electric solenoid to its retaining bracket.
- Position the assembled valve frame setup into the hood opening and secure it with six self-tapping screws.
- Insert the firewall grommet and feed the tan-colored wire from the wiring harness through the grommet.
- Attach the tan wire terminal to the solenoid via the air cleaner hole in the center of the hood.
3. Assemble and Install the Hood Door
- Attach the two hood door supports using the supplied bushings and screws.
- Ensure the door supports are loose enough to allow the door to open and close freely.
- Lay the hood door into the hood opening and secure it with four self-tapping bolts (two on each side).
- Use washers to shim the door supports as needed for proper alignment. The hood door should sit flush with the hood surface and have a 1/16" clearance.
4. Attach the Vacuum Actuator
- Insert the vacuum actuator into its support and secure it to the hood with self-tapping bolts.
- Connect the vacuum actuator throw to the cowl hood door using the supplied screw.
5. Install the Hood Screen
- Attach the cowl hood screen to the rear of the hood opening with eight self-tapping screws.
6. Connect the Wiring
- Attach the air cleaner intake valve relay assembly to the firewall using a self-tapping screw.
- Route the tan-colored wire from the solenoid through the wiring sheath on the firewall.
- Connect the tan and brown leads from the wiring harness to the air control valve solenoid switch near the gas pedal.
- Attach the braided section of the harness to the car’s existing wiring under the dashboard.
7. Final Assembly
- Install the cowl induction spacer assembly on top of the carburetor to elevate the air cleaner into the cowl hood opening.
- Attach the cowl induction air cleaner flange and seal kit.
- Route a 1/4" rubber hose from the vacuum actuator to the vacuum port on the intake manifold.
Reattach the Hood
- Carefully reattach the hood with the help of a friend.
- Align the hood with the fenders by lightly tightening the bolts, gently closing the hood to check fit, and making adjustments as needed.
Performance Gains
While the cowl induction system doesn’t increase horsepower, it provides a legendary look and action, with the hood door dramatically opening under full throttle.
Final Steps
Fire up the engine and take your Chevelle for a spin. Watching that cowl hood door snap open as you hit full throttle is a sight every muscle car fan dreams of!