LokJaw’s Whipple-supercharged 6.6L Duramax needs a lot of air, but the front of the truck is already packed with a radiator, low temperature radiator, and A/C condenser. The fix is a pair of custom Ram-Air intake housings built into the core support, with the filters breaking through the support so the incoming grille air is captured instead of bleeding around them. We shaped the housings to bring air in through the headlight/grille area, added a scroll-style entry to help throw rain outward before it reaches the filter, and kept the whole layout serviceable so the filters can still come out without doing something ridiculous. That’s the real job here: feed the supercharger the air it needs, keep the cooling stack working, and make the package fit like it belongs there.
The video opens with the challenge of packaging Lockjaw's front-end cooling and intake hardware into a radiator core support that would normally be a simple structure. In this truck, the core support has to carry the usual front-end equipment while also accommodating two large custom Ram-Air intake housings. The team describes it as the classic problem of fitting ten pounds into a five-pound bag. Even at the mockup stage, the available space is clearly tight, and every component has to be positioned with both airflow and serviceability in mind.
The first major task is laying out the cooling package. The truck receives three primary heat exchangers at the front: the engine radiator, a low temperature radiator for the supercharger cooling system, and the air-conditioning condenser. The low temperature radiator is described as essentially a thinner, slightly smaller version of the engine radiator. With the parts in hand, the team begins mocking them into place to determine bracket requirements, identify any interference, and see whether any fittings or surrounding structure will need modification.
The intended stack order is established as engine radiator, then low temperature radiator, then condenser at the front. This arrangement is not arbitrary. The team explains that placing the condenser all the way in front produces only a small heat rise in the air passing through it, which preserves good air-conditioning performance. If the condenser and low temperature radiator were swapped, the low temperature radiator would create a much larger heat rise before the air reached the condenser, reducing A/C effectiveness. They accept a small penalty in air temperature through the low temperature radiator for the supercharger system in exchange for keeping the cab air colder.
Once the heat exchangers are positioned, attention turns to mounting hardware. The upper mounting strategy uses an existing lip, likely with screw holes and rubber isolators on studs, while the lower mounts pick up from a flange below. The fabrication is expected to be straightforward, but the team still takes time to measure carefully and decide how best to build the brackets.
They settle on steel brackets, discussing 12-gauge or 14-gauge material, with bends incorporated where possible for a cleaner appearance. After measuring directly on the truck, the bracket shapes are drawn in CAD. Separate pieces are designed to support the low temperature radiator and, in front of it, the A/C condenser. These parts are then cut on the Torchmate and bent on the finger brake. With the finished brackets in hand, the low temperature radiator and condenser can be bolted into place, completing the basic cooling stack installation.
With the cooling package mounted, the next major engineering problem is routing the intake system through the radiator core support. The truck uses a dual-headlight arrangement in the grille, and one of those headlight locations is repurposed as the Ram-Air entry point. This ties directly to Gale's earlier discussion of the supercharger intake system and also references his historical use of ram air through a headlight opening on his Duty Back at the lakes.
The air filter is positioned so that it breaks through the plane of the radiator core support. That creates a sealing challenge: airflow must be prevented from bypassing the intake opening, because the goal is to capture the ram effect while still forcing the rest of the incoming air through the radiator, condenser, and charge-air-cooling hardware. The team is careful not to create a design that is difficult to service. They explicitly want the filter to be removable without disassembling unrelated parts or resorting to awkward procedures. The intended service method is simple: remove the tube, then pull the filter out.
The intake air box itself is designed around a scroll-shaped internal path. Looking down on the filter layout, the Ram-Air entry point feeds into a curved passage that wraps around toward the filter. A shield is planned near the inlet, following Gale's earlier explanation, to reduce the chance of rain being ingested directly into the engine. The idea is to use the momentum of the incoming air to fling water outward while the air continues around the scroll and into the filter.
The transition from the round inlet area to the air box shape still needs to be developed, and the team notes that this piece may be 3D printed. Downstream of the air box, large 5-inch tubes will feed the supercharger inlet. The air box components are initially laid out as flat sheet-metal parts that will eventually become a formed assembly mounted against the core support and aligned with the grille opening. Some pieces are simple constant-radius forms suitable for the slip roll, while others use variable-radius but still non-compound curves, making them more difficult but still manageable to fabricate from sheet metal.
As fabrication proceeds, the air box begins to take shape from the flat patterns. The team notes that the assembly is mostly complete, though still unfinished and open in places. Even in this intermediate state, the structure appears substantial, effectively enclosing and protecting the filter. The work reflects the complexity of the shape: although the curves are not compound, they still require careful forming and fitting to achieve the intended geometry.
At this stage, the project is handed off in part because of workload. With Sean occupied by Lockjaw and other projects, additional help comes in to finish the remaining core-support and air-box integration work. That includes cutting the remaining overlay pieces on the Torchmate, preparing the core support openings, and fitting the air boxes into the structure so the assembly can be returned for final fabrication.
Once the cut pieces are test-fitted, the team discovers that the original reference for vertical positioning was not ideal. The drilled holes ended up slightly low, visible just through the edge of the new cut piece. That means the incorrect holes have to be patched and the mounting points redrilled. Because there appears to be a doubler in the structure, welding in captive hardware would be difficult, so square nuts on the back side are considered instead. The square shape would allow the nut to bottom against the surrounding surface and resist rotation during assembly.
The order of operations is also revised. Since the air box itself occupies part of the core support opening, the team decides to cut the new shape first rather than weld on the overlays and then try to remove material afterward. The two main air-box openings are rough-cut, then refined with additional trimming and filing. Once the air box sits properly in the opening, the new overlay pieces can be positioned around it. The upper overlay and two lower overlays redefine the opening shape and restore structure around the new intake passage.
After extensive filing and fine-tuning, the air boxes are finally fitted into the core support. The result is a very tight gap around the cut lines, tight enough that additional trimming may still be required after welding. On the engine side, the overlays are tacked in place and establish the final contour of the opening. The new shape preserves a straight upper line, then tapers off, while the lower portion is cut to accommodate the 5-inch intake tube.
The team is pleased with the fitment, even though the process took longer than expected. The revised core support is somewhat heavier because of the added overlay material, but the finished integration looks clean and purposeful. At this point, they still need to compare the installed pieces against the CAD model and determine whether more front-side tack work is needed before handing the assembly back to Sean. The episode closes with the air boxes successfully installed in the core support and a preview of additional sheet-metal work and the upcoming digital dashboard in the next installment.