1971 Plymouth Duster Receives a Hood Scoop to Cover the Hellcat V-8

By Ron Covell – Photography By BBT Fabrications

There are many reasons why a car might need a hood scoop. You may require additional cool air inside the engine compartment. Sometimes, the engine has an induction system that rises above the hood line.

02 Supercharged HEMI engine under the hood of the custom 1971 Plymouth with clean fabrication — This 1971 Plymouth Duster has been fitted with a Dodge Hellcat engine. It fits the engine compartment reasonably well, but the supercharger protrudes above the hood line. A custom-built scoop will provide the needed space while adding some style.

On this 1971 Plymouth Duster project being built at BBT Fabrications, they installed a Dodge Hellcat engine, and the blower was taller than the hood. In this article, we’ll show how a scoop can be made for virtually any hood, and you can modify the construction details to suit your particular car.

03 Underside of a fabricated hood showing intricate structural design for the 1971 Plymouth build — The first step is cutting away the hood’s inner structure where the opening will be. Lines are drawn to guide the cutting.

One of the goals of this project was to retain the flavor of the original car, which has a nice raised “plateau” going down the center of the hood. They decided to reverse this detail in the scoop, making a valley but keeping the width and tapering the same as the original hood. The car has a chamfered detail at the top of the front fender and door, and the sides of the scoop were positioned at an angle that complements that feature. Details like this go a long way toward making a scoop look like it belongs to a particular car, and it is important to give these styling cues sufficient thought before any metal is cut.

04 Modified hood structure with a clean cutout for improved engine clearance and airflow — A die grinder with an abrasive cutoff wheel quickly cuts the structure away.

With the rough design in mind, it was time to delineate the shapes and dimensions of the scoop. BBT uses a set of metal sweeps to check contours for sheetmetal panels. After trying several different radii, they settled on a 32-inch radius curve, which established the angle for the leading and trailing edges of the scoop.

05 Close up of rust repair and outlined markings on the 1971 Plymouth hood metalwork — Now, the hood skin is marked for cutting. Careful measurements are required here, so the opening is no larger than necessary.

Having a target to aim for, the center valley of the scoop was the first part to be formed. A piece of aluminum sheetmetal was cut to the correct length and tapered, and the edges were folded with a bending brake. Next, the panel was contoured to match the curvature of the sweep.

06 Custom hood showing supercharger intake wrapped in protective blue film during fitting — With the hood placed back on the car, the opening can be checked against the supercharger. Everything is looking good so far.

Next, an aluminum sheet was cut to make the raised sections that fit next to the center valley. These were domed very slightly and contoured to match the sweep.

07 Rear view of a 1971 Plymouth hood highlighting smooth metal fabrication and structural braces — A 32-inch radius sweep was chosen to set the contour for the center of the new scoop. Spacers were selected to provide the proper clearance.

The sides of the scoop were formed next, taking care to match the angle of the chamfer at the top of the fenders. Once properly shaped, these pieces were joined to the center panels.

08 Custom fabricated metal strip designed for the hood or body of the 1971 Plymouth project — A piece of aluminum was bent in a brake, forming flanges on both sides of the scoop center. Then, the panel was arched to a 32-inch radius.

To ease the complexity of fabrication, the rear corners of the scoop were formed as separate pieces. These were fitted into place, and the rear wall of the scoop was made to bridge the gap between them.

09 Close up of a smoothed brushed metal section possibly a panel or trim piece for the build — Two additional aluminum pieces were shaped and then welded to the center portion, creating the raised areas of the valley in the center of the scoop.

Last, a mounting flange was added to the bottom of the scoop, taking care to match the contour of the hood, both front-to-back and right-to-left.

10 Handcrafted hood panels showing brushed aluminum texture for the 1971 Plymouth custom project — The sloped outer pieces are added, the three centerpieces are formed, and the metal is finished.

Reworking the inner hood panel, which was separated from the hood top to facilitate fabrication, required a lot of effort. The photos detail these extensive modifications, with the goal of making the panel appear factory designed.