Scott Birdsall from Chuckles Garage in Santa Rosa, California, needed more power for his tow rig. Scott’s fun truck is the 1,200-plus horsepower “Ol Smokey” Cummins-powered ’49 Ford, so it seemed a little odd that he was driving around his stock ’97 Dodge Ram 3500 as a daily driver. Now that Smokey is complete, it’s time to perform a little power surgery on the dualie.
An aftermarket turbocharger, injection pump, and injectors will be added to the ’97, but the truck needs supporting modifications before those upgrades. The stock fuel system, air intake, and exhaust are all designed around the 5.9L Cummins engine’s 215hp rating, and they will all be restrictions on the powerplant as horsepower and torque increase.
The stock airbox is the first piece to go, as it will be replaced by an Airaid MXP Series intake system. This airbox not only outflows the stock setup, but it can still be used with an upgraded turbocharger. To vet the engine gases, an aluminized MBRP 4-inch exhaust is being added, along with a 5-inch tip. The final modification is a 165-gph 4G lift pump from PureFlow AirDog that replaces the stock lift pump and filter assembly.
| The first modification involves replacing the ’97 Dodge Ram 3500’s stock air-intake assembly. While the original airbox is fine for 17 to 19 psi of boost, it can be a power-robbing restriction when airflow increases. On modified diesel engines, we've actually seen stock filter minders get sucked flat after a bigger turbocharger is added!
Of the three products, the intake system is the easiest to install, as it only took Scott about 30 minutes to assemble and bolt on. The exhaust system takes a bit more time because of the cutting and welding involved, and the lift pump is probably the most time-consuming item to add because the Dodge’s fuel tank has to be dropped in order to run fuel-feed and return lines.
With these basic pieces installed, there is a noticeable difference in how the engine runs and the truck drives. The turbocharger is much louder, with a cool whine present under acceleration. The exhaust note is also sharper, without being annoyingly loud or droning. Finally, the extra fuel pressure from the lift pump helped take rear-wheel power to 200 hp. Scott is very upfront about his ultimate power goal: He wants the Dodge Ram to have 600 to 700 hp that’s ready for towing. Now he can rest easy knowing his rig is set up with an air-intake system, exhaust, and fuel pump that will support any future mods in store for the 5.9L Cummins.
| The factory intake hose is removed by loosening clamps that secure it to the turbo. The airbox is then removed from its original studs, and the much larger Airaid unit is installed in the same position.
| Airaid’s huge tubular U-bend snakes around the battery and alternator and supplies air to the turbocharger. The tube is secured to the box first, then it’s connected to the turbo with an included flexible hose.
| Airaid includes a washable, reusable, high-flow Premium filter with its cold-air system. To the right side of the airbox is the heat shield, which protects the entire assembly from radiating exhaust heat.
| Not only is the engine bay’s appearance much improved with the Airaid MXP, but the new intake assembly is able to support more than three times the engine’s stock horsepower.
| The PureFlow AirDog’s II-4G fuel system includes a 165-gph pump, filters, lines, mounts, and fittings—everything needed to replace the stock pieces.
| The pump is preassembled as much as possible on the workbench before it’s bolted onto the truck.
| It's best to replace the lift pump with the fuel tank nearly empty, as it has to be dropped to facilitate connecting the return hose and draw straw. While the tank is removed with just a couple of straps, it can be heavy and awkward to handle if it’s full of fuel.
| The lift-pump assembly is mounted on the truck’s framerail, up and as far out of the way as possible. An isolator is included to help muffle pump noise.
| One of the final steps involves running hose from the AirDog pump along the frame and straight to the injection pump, which bypasses the stock fuel-filter assembly.
| Once everything is installed, a transmission jack is used to lift the fuel tank back into place. Scott is careful not to stretch or pinch any lines on the way up.
| MBRP’s mandrel-bent 4-inch exhaust system includes a downpipe and a 5-inch tip. Scott opted for the non-muffler exhaust, as he notes that he “likes to hear his diesel.”
| The ’97 Dodge Ram 3500 already had some sort of aftermarket exhaust. The old piping included a big, round muffler that Scott pitched when making the switch.
| Positioning the exhaust system is time-consuming but not incredibly difficult. Sufficient firewall, axle, spare-tire, and chassis clearance must be confirmed before everything is welded into place.
| Thinking ahead, Scott took the step of adding a V-band clamp immediately after the downpipe. Doing this facilitates changing the pipe and turbo without having to redo the entire exhaust system.
| The new MBRP exhaust was a big improvement in sound, performance, and looks.
| Without turning up the air (with a bigger turbo) or fuel (injectors), we didn't expect record gains from the Dodge Ram’s 5.9L 12-valve Cummins engine. Still, the basic-upgraded powerplant managed to generate 200 hp, which is impressive, given its 215 flywheel-horsepower rating from the factory.