The Cummins 6.7L will take almost anything that you can throw at it when it comes to performance modifications. But while the engine is as tough as an anvil there are better ways of doing things—a smarter way of reaching your horsepower goals.
From quicker response, to lower EGTs, better use of fuel and ultimately more horsepower, airflow is the main ingredient. There are so many areas where you can increase the flow of air into the engine, but for this story we’re going to focus on the intake manifold (sometimes referred to as an intake elbow or intake horn).
The stock intake manifold on the 2007.5-2017 Ram is in plain and simple terms a bottleneck. No matter what modifications that you’ve done before, this scrawny part won’t really matter as airflow will slow down and heat up due to its design. Even if you’re running a compound turbo system making big boost your response time will suffer and you won’t realize its full potential due to the poor aerodynamics inside the manifold.
So, it makes sense to rip that thing off and switch to something better, but with so many choices available which one do you choose?
We spoke with Gale Banks of Banks Power in Azusa, CA, about the unique solution that they’ve come up with.
“To understand the importance of intake elbows we first have to have a discussion about air flow and air density,” explained Gale. “Increasing intake airflow is all about increasing MAD (manifold air density). You do that and now you can mix additional fuel with it.”
Gale has been in the performance business for some time, so he knows what he’s talking about. Not only is he celebrating his 60th year in the performance aftermarket, he’s been working at it since the time he sold his first engine as a teen in high school.
“It all started in 1954 when my dad asked me to replace the head gasket on my mom’s ‘31 Ford Model A,” Gale recalled. “It was a little 4-cylinder, an L-head engine, and made a whopping 90 horsepower, effectively doubling its output. By the time I was done I had replaced the single updraft carburetor with two downdraft racing carburetors.”
Gale then converted the engine to overhead valves on the intake valves. He then built his first header.
“I learned an awful lot in the process about the tools a hotrodder uses,” Gale said. “But I wanted to know a lot more about what’s happening when I now open the butterflies on those two carburetors rather than a smaller single carburetor. I had found I had a higher pressure in the intake manifold at wide open throttle. So all I knew is if I didn't have the air I couldn't mix the fuel with it.”
Gale realized that if he didn't have enough air he couldn't win the race down at Lions Drag Strip in Long Beach, and he wanted to go to the dry lakes and Bonneville at higher altitude.
“There’s not much air up there,” he said. “I really had to get some mastery of airflow. So around 1956 I came across a wartime report from World War II from NACA (National Advisory Committee for Aeronautics), the predecessor of NASA. It was a report on pressure lost in ducts and elbows. It really went into detail on something that is absolutely and completely valid all the way through my career, and that is: if you’re building an intake manifold and you’re making bends in it, or you’re building ducting and you’re making bends that use of a round piece of pipe, especially if you're trying to produce a whole lot of air flow through that round piece of pipe, that's not the best way to do it.”
Gale is not one to mince words on the subject of performance. Using this knowhow Gale saw a way to improve performance on the Cummins, and that’s where the Monster-Ram intake manifold comes in.
There are a lot of intakes that may resemble it, but looks can be deceiving. Gale has poured all his knowledge into this manifold, and the results speak for themselves.
“Well, we start in CAD, and we know where this needs to be and we know where we want this to be,” Gale said as he pointed to the various curves on ports on the intake horn. “We know where the hood is at because we’ve gone in there and digitized the engine bay. It’s all in software, and it's all in our CFD (computational fluid dynamics) test of the model that we build as well.”
Bottom line, Banks generate it in the computer and then flow it in the computer.
“Once we’ve got the design and flowed it we go to the 3D printer and we make a model of it full-sized so that we can now take out and see if our CFD evaluation of the flow holds up on the flow bench,” he said. “On the flow bench we know we have a winning piece before we ever pour any aluminum whatsoever.”
This approach gives Banks an advantage as he can use all the given area to design the part that best uses the available area and to contour the intake for the best airflow, but he didn’t stop there.
“While we found that we were getting great initial results in our digital testing, there were more gains to be had if we were to move the No. 1 fuel line, opening up valuable space for the intake’s larger footprint,” Gale said. This would end up being the game-changer.
“We didn't want to compromise our design, so we went the extra mile and designed an injection line that goes up and over the intake, and it's manufactured by a major OEM fuel injection supplier,” Gale explained. “It's not made in the back room with a hand bender.”
Banks offers two versions to the Monster-Ram—a 3.5-inch inlet and 4-inch inlet, both CNC’d and available in red or raw aluminum for customizing.
“We’ve seen our customer paint them blue, orange, purple and every color of the Skittles rainbow,” he said. “And, while the 3.5-inch inlet version picks up 474 CFM, or 110 percent in flow over stock, the 4-inch gains 576 CFM, an astounding 133 percent more than the stock Cummins intake.”
The best part is that it’s a completely bolt-on part requiring no modifications. Both versions provide quicker throttle response, raises boost without increasing pressure, uses all stock mounting and sensors, has two ports optimized for the atomization of water-methanol or nitrous and has four 1/8-inch NPT ports for additional injection or sensors.
With all this optimization, expandability and ease of installation, the advantage is yours for the taking.