511 Rear-Wheel Horsepower for Only $25,000

Engine Module and Monitor
The single-best bang-for-buck diesel modification is an engine-control module. This job used Edge Products' new Cummins Juice With Attitude system. It offers five different power levels that add 50 to 120 hp and 150 to 350 lb-ft on "standard" Cummins ISB ETC applications, and 40 to 95 horses on H.O. ETH trucks. The Juice black box intercepts the signals between the truck's computer and the engine to maximize efficiency and power by controlling fuel supply, timing, and turbo boost.

The system's Attitude in-cab controller serves two functions. First, its backlit LED readout replaces aftermarket EGT (exhaust gas temperature) and boost gauges. Combined with its thermocouple, the Attitude can be programmed to defuel the engine at preset EGT levels for idiot-proof durability. The Attitude switches among the Juice's five power levels on the fly to accommodate towing, cruising, or flat-out hauling ass as needed.

Fuel Injectors
Diesel Dynamics has tested countless Cummins high-flow fuel injectors over the years--so many that they can now swap out a set in as little as 14 minutes. The engineering challenge here is to maintain proper fuel and cylinder pressures, so simply hogging out the nozzle orifices isn't the answer. In the past, substituting injectors intended for other applications has made power, but now there's a higher-tech solution: Diesel Dynamics' Jammer injector line combines OE Bosch injector bodies with precision-machined nozzles having eight orifices instead of the stock seven. The manufacturing process also matches flow rate to within about 1 percent among injectors. (The stock injectors can vary as much as 11 percent per set.)

Jammers make more power through better atomization, faster fuel flow, and an enhanced spray angle. Diesel Dynamics offers them in five performance stages, ranging from the 60hp Stage 1 to the 175hp Stage 5. Stages are distinguished by orifice diameter, spray angle, pop-off pressure, and price. For this buildup, Stage 3 Jammers were chosen to add about 150 hp when triggered by the Edge Juice module. Another reason that Cummins Rams are popular diesel hot-rodding raw material is that the injectors are easily accessible; mechanically inclined Cummins owners should be able to swap out their injectors in two hours or less.

Max-Boost Turbocharger and Manifold
Doubling the stock power also requires a bigger turbo. The Cummins H.O. ETH is factory-equipped with an HX-35 turbo in a 10cm2 housing for faster spool-up than the standard-output engines. To increase airflow and thus reduce EGT in 325- to 500hp buildups, Diesel Dynamics uses its HX-40 Max-Boost turbo.

The turbocharger is preassembled with a restrictor elbow and wastegate spring to mechanically regulate boost pressure to 40 psi. It's also clocked for bolt-on installation and fitted with a 4-inch downpipe. The turbo bolts to the ATS manifold, OE intercooler, exhaust downpipe, and lower oil line. The unit must be primed with oil before the upper oil line is connected.

This unit receives a modified bearing package for durability, and Diesel Dynamics mechanically regulates the escargot's wastegate to open at 40 psi (compared to the OE 21 psi). Increased airflow drops EGT by about 250 degrees F and adds an extra 25-plus hp and 50-plus lb-ft. Between the turbo and engine is an ATS exhaust manifold, which uses a three-piece design with expansion joints to handle near-instantaneous temperature variations between 700 and 1,400 degrees F. The manifold is engineered to reduce backpressure and improved turbo spool-up.