The real problem on the Ram 6.7L Cummins is not just airflow in general. It is air-density loss right where compressed, cooled charge air is supposed to enter the engine. The stock intake horn and grid-heater layout create a major restriction, and that restriction forces the turbocharger to work harder, raises turbine backpressure, and gives away response and efficiency. Our Banks Monster-Ram Intake and Killer Grid Heater Upgrade fixes that by opening the path from the throttle into the intake, replacing the stock grid-heater arrangement with a high-flow intake plate and cylindrical heater strategy, and rerouting the fuel line so the outlet can stay clean and symmetrical. That is why it outflowed stock and every tested competitor in mass-air testing, reaching 72.7 lb/min at 20 in. of water versus stock at 38.6 lb/min. What matters on the truck is simple: less restriction after the intercooler means better engine breathing, less turbine drive demand, quicker time-to-boost, and more headroom whether the truck is stock or tuned. It is also the only 50-state emissions compliant high-performance intake manifold called out here for all Ram 6.7L Cummins pickups from 2007.5 to current.
Banks introduces the new Monster-Ram intake manifold for 2007.5-current Ram Cummins applications. It is presented as the only high-performance intake manifold in this segment with 50-state emissions compliance. The product is positioned as the latest step in Banks' long development history with the common-rail Cummins platform, a history that goes back to before the engine was even offered in pickup trucks. Banks notes that it worked with Cummins on a world speed record effort in 2002 using this engine family, and that it had already built a special racing intake manifold for the same fundamental reason behind the Monster-Ram: improving the air density delivered to the intake valves.
The technical argument begins with a distinction between airflow measured in cubic feet per minute and airflow measured as air mass. Gale emphasizes that CFM can be misleading on turbocharged engines because the volume changes as the air is compressed, while the mass flow remains essentially constant through the system. On naturally aspirated engines, CFM was a useful shorthand for engine efficiency, but once supercharging or turbocharging enters the picture, density becomes the more meaningful metric.
Using the Ram 6.7-liter Cummins as the example, Gale explains that ambient air may enter the intake system at roughly 1,200 CFM, yet only about 400 CFM may be flowing into the engine after compression. That does not mean airflow has been lost; it means the air has become denser. Ambient air density is described as about 72 pounds per 1,000 cubic feet, and when the turbocharger compresses the charge, the same air mass occupies less volume. For that reason, Banks focuses on engine mass flow in pounds per minute rather than CFM. On early 6.7-liter engines, mass flow was in the mid-40-pound-per-minute range, around 45 lb/min. Later models are said to run about 48 to 52 lb/min, and Gale reports dyno testing his 2020 high-output truck at 52.4 lb/min at 400 horsepower. Across the 2007.5-current 6.7-liter range, he treats 50 lb/min as a useful nominal figure.
From there, the recap follows the intake path in order. Ambient air enters through the Banks Ram-Air system for 2019-up Ram Cummins trucks, passes through the large filter and feed tube, and reaches the turbocharger compressor. The compressor is driven by the turbine through a common shaft, and the turbine itself is powered by exhaust energy in the form of exhaust pressure and temperature. Gale points out that this turbine-driving energy ultimately comes from the crankshaft, because the pistons must push exhaust gas out during the exhaust stroke. In his framing, any reduction in the horsepower required to drive the turbine can free more usable power at the flywheel, torque converter, transmission, and wheels.
The turbocharger is described as a density machine because it raises air density by compressing the intake charge. After compression, the air moves through a large Banks boost tube into the charge air cooler. The charge air cooler shown in the display fits 2013-2018 engines, and its role is to reduce the temperature increase caused by compression. Cooling the charge further increases density, again without changing the underlying mass flow. From the charge air cooler, the air travels through another low-restriction boost tube into the factory throttle, which remains necessary for air and exhaust-gas mixing under certain operating conditions. Finally, the air enters the Monster-Ram and then the intake manifold.
Banks' broader design philosophy is that only two devices in this system should intentionally increase air density: the turbocharger and the charge air cooler. Everything else should minimize density loss. That is why Banks emphasizes large boost tubes, carefully developed charge-air-cooler end manifolds, and a 3.5-inch outlet into the throttle body to reduce pressure loss and maintain a favorable pressure profile across the core.
To quantify intake-manifold restriction, Banks did not use the flow bench in the conventional aftermarket sense. Instead, the bench was configured as a variable mass-flow air pump. The setup used a bellmouth feeding a tube into a mass air flow sensor, then a boost tube into the throttle body, the Monster-Ram, and a billet plate representing the intake-manifold interface. Temperature, pressure, and differential pressure were measured across the MAF sensor, and room conditions were also monitored.
The key measurement was air-density loss through the intake hardware. Banks logged data with iDash DataMonster instrumentation and used an ambient sensor to record room temperature, pressure, and humidity. The stated goal was not simply to compare raw flow numbers, but to determine how much density was being lost between the incoming air and the point where it entered the engine. Banks says it tested not only the Monster-Ram, but every competing product it could obtain.
The comparison begins with the stock intake horn and stock grid heater used for cold starts. Gale describes the stock arrangement as highly restrictive, with a small outlet and a basic flow path that makes a sharp horizontal turn and then bends downward into the grid heater. That awkward geometry is attributed largely to the need to clear a fuel line.
Banks also tested an aftermarket elbow identified as a Shibby unit purchased on eBay, even though it had reportedly been discontinued. Gale criticizes its relatively flat transition and the way the air is forced into a geometry that still has to clear the stock fuel line. In his view, the outlet alignment into the heater is especially poor. Another tested product was an AFE intake elbow, which also uses a notched outlet to clear the fuel line. That part includes an internal turning vane, marketed as part of a BladeRunner concept, but Gale argues that any device used to redirect airflow also costs pressure and therefore hurts density.
Banks took a different approach. Rather than work around the stock heater and fuel-line packaging, it redesigned the heater solution entirely. The Monster-Ram uses a cylindrical heater, similar to those used on other diesel engines, threaded into the manifold body. It also uses a billet intake plate supplied with the kit. Gale says this billet plate introduces essentially zero restriction and zero density loss. To eliminate the packaging compromise that affected the other designs, Banks also created its own fuel line so the outlet could remain symmetrical rather than being notched around the factory line.
Banks plotted pressure drop in inches of water against mass airflow in pounds per minute over a range from 10 to 90 lb/min. At 15 inches of water pressure drop, the stock intake flowed about 35 lb/min and still had not reached the nominal 50 lb/min target even by roughly 35 inches of water on the chart. The Shibby elbow, tested with the stock heater plate, performed worse than stock at 31.7 lb/min, a reduction of 3 lb/min or 8.6 percent. The AFE unit reached 36.5 lb/min, a gain of 1.8 lb/min or 5.3 percent over stock.
The Monster-Ram, with its own integral heater arrangement, reached 60.9 lb/min at the same 15-inch pressure drop. That represented a gain of 26.2 lb/min over stock, or about 76 percent. At 20 inches of water pressure drop, the stock setup increased to 38.6 lb/min, the Shibby to 36.5 lb/min, and the AFE to 41.8 lb/min, which Banks characterizes as an 8.1 percent gain over stock. The Monster-Ram reached 72.7 lb/min at 20 inches, an 88.3 percent improvement over stock.
Because some critics might argue that the billet intake plate gave Banks an unfair advantage, Banks retested the competing elbows with a billet plate as well. In this configuration, the cold-start heater was removed from the competing setups, while the Monster-Ram still retained its own heater solution.
At 15 inches of water, the stock elbow with billet plate flowed 35.1 lb/min. The Shibby improved to 39.5 lb/min, which Gale interprets as confirmation that its alignment with the stock heater had been especially poor. The AFE reached 44.4 lb/min. The Monster-Ram remained at 60.9 lb/min. Relative to stock in this billet-plate comparison, the Shibby showed a 12.5 percent gain, the AFE a 26.5 percent gain, and the Monster-Ram a 73.5 percent gain.
At 20 inches of water, the stock setup rose to 41.6 lb/min, the Shibby to 46.6 lb/min, the AFE to 52.3 lb/min, and the Monster-Ram to 72.7 lb/min. Gale summarizes those gains as roughly 12 percent for the Shibby, 26 percent for the AFE, and 75 percent for the Banks unit. In other words, even after removing the stock heater restriction from the comparison, the Monster-Ram still maintained a large advantage.
Banks then explored a more fundamental question: how much restriction comes from the elbow itself versus the throttle body. Testing the throttle body alone produced about 59 lb/min, which was described as a 42 percent improvement over stock. What surprised Gale was that the Monster-Ram actually outperformed that result. His conclusion was that the Monster-Ram does more than simply avoid restriction; it improves the exit conditions from the throttle body into the engine by diffusing the flow, turning it about 120 degrees, and delivering it into the manifold with more uniform pressure and velocity.
Banks even fabricated what Gale calls a perfect air diffuser for the throttle-body exit to see whether it could outperform the Monster-Ram. One path discharged straight to ambient air, while the other passed through a 120-degree bend into ambient air. Even in that comparison, he says the Monster-Ram still prevailed. For Gale, that made the result one of the strongest product-development victories of his career.
The practical claim is that a less restrictive intake path reduces the exhaust energy needed to drive the turbocharger. If the intake side is less restrictive, the turbine does not need to work as hard, backpressure on the pistons during the exhaust stroke is reduced, and less fuel is required to make the same horsepower. That can improve fuel economy. If the engine is tuned for more output, the lower restriction can also support more power at the same fueling. Banks says the system flowed easily to 90 lb/min on the bench, suggesting substantial headroom for tuned applications.
Gale also describes a throttle-response and time-to-boost benefit. Because the turbo shaft speed required at a given power level is lower with the freer-flowing intake, the turbo has less speed to gain when the driver requests more power. In his explanation, that shortens the time between throttle input and the boost, or more precisely the mass airflow, needed to respond.
The Monster-Ram kit is said to include the revised fuel line, billet intake plate, a cosmetic heat shield for the EGR system, fittings, bolts, and even thread locker. It is offered in Banks red or raw aluminum for customers who want to paint it. The recap closes with the broader point that the product is intended as the intake-side answer for both stock and tuned Ram Cummins trucks while preserving emissions compliance and cold-start functionality.