The real problem here was not making boost. It was controlling what the blower was doing at idle. With the original setup, pressure built up when the engine was just sitting there, and that caused blowback through the screw blower. That heated the intake charge, hurt responsiveness, and made the system less stable than we wanted. We fixed it by changing to a 3.8-liter billet Whipple Gen 5 and adding an electronically controlled bypass that vents excess pressure at idle. That gives the boost air somewhere to go, keeps more air moving through the blower, cuts down the blowback issue, and helps hold intake temperature in check. Then when throttle comes in, the valve closes and the engine gets boost immediately. That is why this engine reacts the way it does. The combination of the supercharger drive, the bypass strategy, the open header-to-collector exhaust path through twin Banks Monster Exhaust System outlets, and full data logging through Banks iDash Pro and MoTeC gives us a diesel that answers the pedal right now instead of waiting to come alive.
The video centers on the first startup of Banks' prototype turnkey diesel engine installed in the LockJaw project truck. After appearing at SEMA as a largely completed display vehicle, the truck returned to the shop for the detail work that had not been finished in time for the show. By the time of this filming, the team had the truck stripped down, set up on blocks, and focused on making it fully operational rather than merely presentable.
The stated goal was straightforward: get the engine ready for its first real fire-up and evaluate how the package behaved. The team emphasized that this was not a cosmetic milestone. They were preparing to run a very serious engine combination, and they wanted to inspect the installation carefully before making noise with it. That meant opening up access, checking systems, and confirming that the truck was ready for a controlled hot run.
Although the truck still looked similar to its SEMA form, much of the progress since then had been in the electrical system. Considerable wiring work had been completed, including grounding between the cab and frame and between the bed and frame. Harness routing and cleanup were also underway so the final installation would be both functional and clean.
The electrical architecture starts with a lithium-ion battery mounted at the rear. It is rated at 3,100 CCA and feeds the system through what was described as a 4/0 battery cable and a 1,000-amp fuse. From there, power is routed to a bus bank that distributes 12-volt supply and provides a substantial grounding bar. The heavy cable then feeds a battery cutoff switch before continuing forward into the vehicle.
Inside the truck, the main control hardware is a MoTeC M142 ECM paired with a MoTeC PDM power distribution module. The PDM functions as a sophisticated fused panel and relay-control center, handling loads such as lighting, 12-volt ignition circuits, electric cooling fans, the charge-cooler coolant pump, the RideTech air suspension system, the transmission controller actuator system, and other modules requiring switched 12-volt power. The truck also uses an ATS cam translator module to manage communication between the Allison transmission controller and the MoTeC system so the two operate seamlessly.
Under the dash, the team installed a MoTeC keypad and four iDash displays along with a MoTeC screen, all connected on a common CAN network. The system was described as fully configurable, with the displays and controllers communicating across the same network. The result is a tightly integrated electronic package intended to support both operation and extensive data logging.
Several practical installation changes were made once the truck was up on blocks and the cab could be squared properly. One issue involved Deutsch connectors that had originally been positioned too close to the headers. After seeing the final relationship between the cab, engine, and exhaust, the team relocated those connectors farther away from the heat they would experience in operation.
They also cut an access opening in the firewall. Because the engine bay is tightly packaged, especially around the rear of the engine and the heat-exchanger hardware, reaching connectors at the back had been difficult. The new access panel made those connections far easier to service.
At the rear of the truck, additional plumbing work had been completed, and the bed sides were tied in more securely. The original bracketry had been considered too flimsy, so the team added structure to support the bed sides properly. One more visible modification was a large opening cut into the bumper to provide Ram-Air. Even though it was mentioned jokingly in the context of idling, it reflects the broader effort to support airflow through the system.
One of the most important engineering changes since SEMA was a supercharger swap. After the truck returned from the show and Jeff Lee began running the engine, the team discovered that intake temperature was rising at idle because of puffback or blowback from the blower. Hot air was effectively being driven back into the supercharger, increasing inlet temperature and degrading the operating condition they wanted.
In discussions with Whipple, they confirmed that screw blowers have an efficiency sweet spot. Below that operating point, blowback becomes more pronounced; above it, the blower speed and mass flow are sufficient to pull air through properly. The revised setup uses a 3.8-liter billet Whipple Gen 5 screw blower. The drive ratio is 3.79:1, meaning the blower turns 3.79 times crankshaft speed, or about 3.8 times if rounded.
Banks also designed the inlet system and blower-drive extension as part of the air inlet path. Ambient air enters through both inlets and air filters, and vehicle speed contributes a small amount of ram pressure, improving feed as speed increases. Gale briefly connected this approach to earlier Ram-Air experimentation, recalling a 1960-era Bonneville setup on a 1953 Studebaker in which he removed a headlight and fed a Rochester fuel injector on a small-block Chevrolet. That arrangement was later banned in competition, but in this truck there is no rulebook limiting the concept.
The purpose of the blower change was to move the system into a lower-speed sweet spot and then evaluate intake temperatures with the revised arrangement. The team expected the new combination to reduce the idle-temperature problem and improve responsiveness.
Changing the blower alone was not the entire solution. The team also concluded that boost pressure at idle needed to be regulated. If idle boost remained too high, intake temperature would stay higher than desired and the engine would become less responsive. Their answer was to give the compressed air somewhere to go at idle rather than forcing the blower to work against a closed condition.
Instead of using a conventional blowoff valve that might recirculate turbulent air back toward the inlet, they chose to vent to atmosphere. The hardware is a Turbosmart eSG50, described as an electronic StraightGate 50 mm valve. Unlike a typical poppet-style wastegate valve, this unit uses a butterfly arrangement in a cast stainless housing and is designed to tolerate extreme pressure. The timing was convenient because Turbosmart had just released the product at SEMA, and the team wanted to test the response speed of its electronic actuator.
To integrate it, they redesigned the top plate of the intake manifold to include a 2-inch outlet at the rear. That outlet is plumbed directly to the StraightGate, with thermocouples installed to monitor temperatures. The valve bleeds off excess pressure directly to atmosphere. At the time of filming, calibration was still being developed. Initial control involved manually adjusting the valve through the calibration, but the long-term plan was for the MoTeC system to command it automatically. In that strategy, the valve would remain partially open at idle and then close as soon as throttle input was detected, restoring boost immediately.
This bypass strategy increases airflow through the blower at idle, reduces pressure ratio across the blower, minimizes blowback, and stabilizes both idle quality and intake temperature. The team viewed that stable idle temperature as a key part of making the engine react instantly when the throttle was applied.
Gale framed the truck's engine as more than a one-off experiment. He described it as the beginning of a major engine program and identified this unit as prototype Banks turnkey engine number one. In other words, the startup was not just about making LockJaw run; it was also an early validation step for a broader turnkey-engine effort.
He also explained what he hoped to hear from the engine. Drawing a comparison to older Formula One Cosworth engines that accelerated so quickly they sounded like fabric being ripped, he said his ideal outcome was diesel response with that same kind of immediacy and high-frequency urgency. The question going into the startup was whether this large, supercharged diesel would deliver anything close to that kind of throttle reaction.
Before attempting to start the engine, Gale followed his standard procedure of cranking for oil pressure first. In the engine room, he said, they normally hand-crank and move oil through an engine before it ever goes into a vehicle. In this case, the truck used a laptop routine to disable firing while the engine was cranked for final priming.
During the priming sequence, the engine built roughly 28 psi of oil pressure. Gale continued cranking for about 10 seconds after pressure appeared to ensure that most of the air had been pushed out of the system. Once satisfied, the team enabled the fuel pump and prepared for startup.
They also initiated data logging before the engine fired. Logging was being captured from the iDash system as well as from the MoTeC controls. The iDash alone was said to be recording 100 channels, reflecting the team's emphasis on instrumented evaluation rather than simply listening to the engine run.
Once the engine started, the first observations focused on basic health and operating values. Rail pressure was good, and engine oil pressure settled at about 55 psi at idle. Idle speed appeared to be around 850 rpm. The engine was configured with a 4,000 rpm redline.
At idle, boost pressure was approximately 2.25 psi with the bypass valve open. Gale also noted that normal rail pressure was around 77,000 psi. Exhaust gas temperatures were described as quite uniform, at roughly 250 degrees, and because this setup did not have turbines in the way, the readings could be interpreted without that additional restriction affecting the exhaust path. The battery was charging properly, and no obvious issues appeared in the initial instrument sweep.
The team let the engine idle briefly to build some oil temperature before applying throttle. This pause was part of the controlled approach to the first run, allowing them to confirm stable operation before testing response.
When Gale finally tipped into the throttle, the reaction was immediate and dramatic. The engine snapped to rpm with a speed that clearly exceeded expectations, and the response prompted an emotional reaction from everyone present. Gale said he had never in his life heard a diesel respond like that. He compared it favorably not only to other diesels but to high-compression big-block Chevrolets with blowers, concluding that this engine stood apart from anything he had previously experienced.
That response was the central result of the video. The combination of the revised 3.8-liter Whipple setup, the idle bypass strategy, the integrated controls, and the detailed finishing work produced an engine that behaved with exceptional sharpness on the pedal. For the team, the first fire of prototype turnkey engine number one was not merely successful because it ran; it was successful because it delivered the kind of instantaneous, aggressive throttle response they had been chasing.