These wheels weren’t drawn as decoration. On LockJaw, we wanted big windows to show the Wilwood brakes, but more importantly to move air through the wheel and across the rotor. The design also works to pull air out of the wheel, creating a low-pressure area under the truck at speed. That means the wheel has a real job beyond holding the tire. At the same time, the shape had to fit the truck. LockJaw wears patina on the outside, but the engineering underneath is highly technical, so the wheel design had to carry both ideas at once: nostalgic at a glance, functional when you look closer.
Dustin Whipple, vice president of Whipple Superchargers, explains that the LockJaw project uses a one-off 3.8-liter front-feed supercharger paired with a custom inlet system. Unlike Whipple's more traditional 3.8-liter layouts, this unit is inverted, with the shaft and pulley positioned at the front. It also uses dual inlets to supply the airflow needed for the intended power level.
Whipple's involvement with diesel applications has been limited, since diesel performance is usually turbocharger-based and therefore outside the company's usual focus. Whipple had previously worked on an older Hummer diesel application years ago, but LockJaw became the right opportunity to revisit the concept. Dustin notes that his long-standing relationship with Gale Banks led to discussions about where the two companies' capabilities could overlap, and the LockJaw diesel project became that opportunity.
The supercharger work drew on lessons learned from earlier testing on a compound-style engine that used a very large intercooler and blower. According to Dustin, that earlier development showed that the same principles could be applied with a smaller supercharger package. The immediate goal was to deliver as much air as possible while keeping charge temperatures under control, leaving the rest of the engine-system integration to the Banks team.
Whipple handled the CAD work for the supercharger itself and advised on the inlet design, while Banks completed much of the CAD development for the dual-inlet arrangement and the manifold that mounts the intercooler. Dustin also says the broader intent is to turn what is learned on LockJaw into a viable product if possible.
He emphasizes that Whipple, like Banks, has long focused on emissions-legal products wherever the application is not strictly for racing. That commitment to working within the rules is presented as a shared philosophy between the two companies. The rotor pack used here is Whipple's current production 3.8-liter rotor set, already used in Mustang and other racing applications, with a related version planned for the Hellcat platform. While future variants are expected, the hardware shown on LockJaw is based on a current production setup.
While the induction system is being developed, the fabrication team is simultaneously pushing through major bodywork under intense SEMA deadlines. One task centers on the upper bed structure. The backside ribs are being built from uniform half-inch strips cut from blanks, and drawings are created so each reinforcement piece lands correctly around hinge overlays and other structural intersections. The plan is to prep all of the pieces, wait for the remaining material to arrive, then weld the assembly together and return it to Sean so it can be installed on the truck.
The process begins with a cut list covering all required sizes and quantities. After the blanks are cut, they are passed to Eric for milling so clearances can be added anywhere another plate or structure interferes. The work is described as pure SEMA crunch, with equipment problems adding to the pressure. A worn gear mechanism on a machine handle fails, forcing a quick repair so the Z-axis can be moved again and machining can continue.
To set up the milling operation, a half-inch by three-quarter-inch aluminum reference piece is used to establish the cutter position. The operator zeros the Z-axis at the top of the half-inch thickness so that removing one-eighth inch from a half-inch-wide bar becomes straightforward and repeatable. The goal is not cosmetic perfection but reliable clearance, with a slight overcut considered preferable to risking interference.
The team also revisits the wheel design for LockJaw. Earlier discussions with Gale established that the wheel could not simply be a basic eight-window design. The wheel had to satisfy both technical and visual requirements. It needed to fit an eight-lug, 8-on-180 bolt pattern, or 7.086 inches in carpenter's terms, while also providing large enough windows to show off the oversized Wilwood brakes behind it.
More importantly, the wheel was intended to actively manage airflow. The design objective was to move air through the wheel, through the rotor area, and out the front face of the wheel. That airflow extraction would help pull air out of the wheel cavity and create a low-pressure region under the truck at high speed. Although the concept of ventilating a wheel is not new, Gale's requirements combined brake visibility, aerodynamic function, and a specific visual character.
Because LockJaw retains a patina exterior, the wheel design needed to feel nostalgic from the outside while still reflecting the highly technical engineering hidden underneath the truck. Several sketch directions are considered. One idea introduces a subtle directional effect so the wheel appears to have forward motion even when stationary. Another explores larger windows and more traditional rectangular curved openings. The favored direction uses the largest practical openings while preserving a vintage feel, and the designer plans to send the sketches to Gale and the team for feedback.
Additional bed fabrication continues as more upper-bed components arrive. Some aluminum overlay pieces can be prepared immediately, but a full-size sheet still has to be picked up from the local metal supplier so the full-length side flanges can be cut. Because the panel is 6 feet wide and the welding table is only 4 feet wide, the table has to be staged carefully so as much of the panel as possible can be clamped during welding.
That clamping is critical because the large sheet is flexible and prone to distortion. The goal is to make it as stiff as possible before welding proceeds. The pace is unusual even by shop standards, with work happening during the day rather than only after hours, simply because there is no time left in the schedule. The emphasis throughout is on preparation: cut what can be cut, fixture what can be fixtured, and keep the project moving despite incomplete material deliveries.
Parallel to the sheetmetal work, the team is converting mock-up hinge concepts into final billet components. Matt had previously developed a simplified hood-hinge geometry, and Quinn is now turning that geometry into CNC-machined parts. The final design keeps the same kinematics but thickens the components, adds machined recesses, and replaces simple through-bolts with a more refined bearing-supported arrangement.
The hood hinges will use ball bearings and shoulder screws, with features machined to fully capture the inner race of each bearing. That should produce a smoother-operating hood linkage system than the mock-up version. The work is still underway late at night, with the team pushing to finish the parts in time for SEMA.
Matt is simultaneously detailing the bed hinges. These carry even more load because the main arm is long and the bed structure is substantial. His plan is to repurpose stock C20 Chevy hood hinges to help open the bed, an approach he likes because it reuses existing parts in a new role. The design also incorporates a heavy extension spring, and the CAD work focuses on getting the geometry, moment arm, and clearances right around the bed structure. The objective is not just to make the bed tilt, but to make it function cleanly and convincingly when displayed at SEMA.
After refining the sketches, the wheel designer settles on a direction that emphasizes fins around the perimeter. These fins are intended to draw the eye visually while also serving the airflow goal by helping pull air through the large windows and spoke openings. The challenge is to preserve the nostalgic overall appearance while integrating clearly functional aerodynamic features.
The resulting concept is meant to fit the truck's dual personality. From the outside, LockJaw still reads as an old patina truck. On closer inspection, however, the wheel reveals the same technical intent found throughout the rest of the build. With that direction established, the design is sent to Gale and the team while additional refinement continues.
As the upper bed structure comes together, the team encounters a fitment issue with a flange on the tub that wraps around the original structure. The desired top wrap conflicts with lower bracing that now sits flat off the bottom, so the flange has to be hammered flat to allow the pieces to sit correctly again. Once corrected, the inner structure for the top half of the bed is mounted in position.
The assembly is located by the shock mounts on the frame, which fixes its position securely. The original stake pocket is eliminated in the process, but the bed sides and outer surfaces are now where they need to be. With that geometry established, the team can begin making the rear tubs. They will create the patterns and flanges now, but they intentionally will not drill the mounting holes until the entire bed system is final-mounted and the tilt mechanism is fully working. Only after all movement and alignment are confirmed will the tubs be drilled and bolted down. The wood bed floor will then sit on top of that completed structure.
The final portion of the recap shifts to finishing details and parts sourcing. Rather than replacing the windshield with a new clear piece, the team decides to reinstall the original green-tinted glass, preserving more of the truck's aged character. The back window is also installed, and attention is drawn to the original factory air-conditioning sticker still present on the glass. That detail suggests the truck was a well-optioned vehicle when new and adds another authentic touch that would be difficult to replicate.
To support the rear bed work, a set of tubs is produced for the back of LockJaw. These are presented as a suitable solution for the truck's rear packaging needs and will integrate with the bed structure once final mounting and drilling are complete. Together, these steps show the project moving from conceptual engineering and fabrication into visible assembly, with the supercharger system, wheel design, hinges, bed structure, and body details all advancing in parallel toward completion.