The real issue here is fuel control at high power, not just fuel volume. When you’re feeding twin high-pressure pumps and pushing toward 3,000 horsepower in a dyno cell, the lift side has to maintain pressure, the regulator has to return excess fuel cleanly, and the filters can’t become the restriction. This setup uses Holley inline billet pumps, a return-style regulator, and fine secondary filtration to solve that problem as a system. The smaller pump is enough for roughly 1,500-horsepower diesel use at the stated pressure target, while the larger 12-1800 pump adds serious headroom with staged operation from its dual gerotor sections. That means one section can run normally and the second can come on only when fuel demand climbs. Just as important, a constant-run pump needs a regulator with enough return capacity to bypass fuel the engine isn’t using. Pair that with proper primary and secondary filtration, and you get stable lift pressure, cleaner fuel delivery, and a supply system that can support both diesel and gasoline work without becoming the weak link.
Gale Banks opens with a specific problem in dyno cell number one: the fuel system feeding the engine from the outside fuel shed is not maintaining enough lift-pump pressure at the twin Bosch CP3.3 pumps. He notes that the high-pressure pumps themselves also have issues, but his immediate priority is to solve the low-pressure supply side first. The goal is to modernize the cell so it can support roughly 3,000 horsepower on diesel.
To do that, he contacted Holley for a complete low-pressure fuel-system package that could support both gasoline and diesel operation in the same cell. His requirements included primary filtration, pumps, return-style regulation, and secondary filtration. On the diesel side, he also plans to incorporate water separation and Banks iDash-related monitoring upstream. From the Holley portion of the system onward, the plan is to run Holley hardware all the way to the Bosch pumps.
The first component he examines is Holley's 12-890 inline pump. It is a single-pump unit rated at 100 gallons per hour. Banks highlights the pump's billet anodized mounting foot, emphasizing that it is a substantial mounting arrangement rather than a thin sheet-metal clamp-style bracket.
He also likes the inline layout. Instead of an awkward inlet and outlet arrangement, the fuel path runs straight through the pump, which makes for a cleaner installation in a dyno cell or a vehicle. The pump uses -8 O-ring fittings on both inlet and outlet. Even though the system will have primary filtration ahead of the pump, the pump also contains an internal screen to catch debris that might have been missed upstream.
Banks explains that the 12-890 is designed to run continuously at constant speed and uses a gerotor pumping mechanism, a design he clearly favors for its technical quality and OE-style durability. He cites a life expectancy of well over 100,000 vehicle miles or more than 3,000 operating hours.
For his diesel application, he says that at 15 PSI the pump will deliver about 90 gallons per hour. Using a brake specific fuel consumption of 0.42 pounds per horsepower-hour, he calculates that this is enough to support approximately 1,500 horsepower on diesel. In his view, that makes the single pump a realistic choice for a street diesel or any application capped around 1,400 to 1,500 horsepower.
He then moves to the larger Holley 12-1800 pump assembly. This unit is rated at 200 gallons per hour, with free-flow capability around 210 gallons per hour, and he recalls that the 200-gallon-per-hour figure is at roughly 8 PSI outlet pressure. Compared with the smaller pump, this is a much more serious piece, using -10 inlet and -10 outlet connections.
Banks notes that the pump contains test fluid from factory validation, which confirms that the unit has been run and checked. The assembly uses four electrical leads because it actually contains two separate gerotor pump systems and two motors in one package. One stage can run by itself for lower fuel demand, while the second stage can be brought online only when needed. He describes a control strategy in which the first pump comes on with key-on, while the second is triggered by operating conditions such as higher boost, nitrous use, or any other condition that sharply increases fuel demand.
In his own dyno-cell application, he says the second stage would likely be controlled by manifold air density, potentially with a mass-airflow overlay if available. He considers that staged operation a major advantage. It provides high flow capability without requiring both pumping elements to run all the time when demand is low. He also praises the compact size and relatively low noise level, attributing that to the OE-type internal design.
A major concern with continuously running pumps is return capacity. Banks explains that if a pump runs all the time, the regulator must be able to bypass nearly the full pump flow when the engine is not consuming much fuel. That requirement influenced his component selection.
He originally asked for the smaller pump, but after realizing that the larger dual-stage pump could be operated one stage at a time, he concluded that he may not need the smaller unit unless the target remains around 1,500 diesel horsepower. Since he intends to go beyond that, the larger staged pump makes more sense.
Holley had recommended a lower-pressure regulator for his 15 PSI lift-pump requirement, one with a range of roughly 4.5 to 9 PSI, but Banks appears to favor a larger regulator body with much greater return capability. The regulator he shows uses -10 inlet, -10 outlet, and -10 return ports, which he sees as important for handling substantial bypass flow. Pressure is adjusted with a lead screw and jam nut. The regulator also includes a 1/4-inch boost-reference provision so fuel pressure can rise 1:1 with boost pressure when needed.
Banks then turns to secondary filtration. Holley recommends about 100-micron filtration on the primary side if the system is being configured for EFI-style supply, while the finer downstream filtration should be around 10 microns. He notes that this level is also reasonably suitable for diesel injectors.
The inline filter assembly he unboxes uses 1/2-inch pipe connections and contains a paper filter element rated to 7 microns. The housing is billet, and he calls out the wall thickness as 0.150 inch aluminum tubing, indicating that it is built to withstand substantial pressure without distortion or failure. Although his immediate diesel lift-pump setup in cell number one will operate at only about 15 PSI, he points out that the same basic filtration hardware can support much higher-pressure feed systems.
That higher-pressure capability matters because Banks plans to use a very similar arrangement in dyno cell number two, where he expects feed pressure requirements up to about 90 to 100 PSI for a Denso injection system. He adds that very high-boost gasoline EFI combinations can approach similar pressures, because fuel pressure must rise with boost in order to maintain the desired injector differential pressure, or Delta P, across the nozzle throughout the engine's operating range.
The 7-micron filter is rated to flow 750 gallons per hour, which Banks considers more than sufficient for the power levels he intends to support. He also gives a gasoline-related flow figure for the larger pump setup: at 90 PSI, the system is good for about 116 gallons per hour. In his view, that provides strong upper-end flow capability for gasoline use as well as diesel.
By the end of the unboxing, Banks is satisfied that the Holley components give him a workable path to solve the dyno-cell fuel-supply problem. The combination of staged gerotor pumping, substantial return-style regulation, and fine downstream filtration should allow him to stabilize lift-pump pressure to the Bosch CP3.3 pumps and support both diesel and gasoline testing.
His conclusion is that this hardware should cover the fuel requirements for both dyno cells for the foreseeable future. For diesel, he sees enough capacity for roughly 3,050 horsepower in cell number one. For gasoline, he also sees strong high-pressure flow capability. The next step is to install the system in dyno cell number one and verify how it performs in operation.