511 Rear-Wheel Horsepower for Only $25,000

Diesel performance used to be an oxymoron. Then "diesel-heads" (generally considered to be morons by the performance industry) began playing with these farm-bred engines. Today, their power claims seem way too good to be true: 700-plus rear-wheel horsepower, 1,600-plus lb-ft of torque and 11-second quarter-miles in 7,000-pound smoke-belching pickups?

A 500hp Challenge
Recognizing the huge bang-for-the-buck performance potential in late-model oil-burners, two diesel-performance specialists, Edge Products and Diesel Dynamics, hatched an idea: Buy a slightly used diesel truck and build it to reliably (some smoke, but no mirrors) put out 500 rear-wheel hp for less than the cost of a new vehicle. Real-world output would be approximately 200 horses more than an off-the-lot '04 and nearly 300 hp greater than the used truck's original rear-wheel numbers.

A '01 1/2 Ram was chosen for the challenge. This vehicle is good raw material because Dodge introduced the 245hp/505-lb-ft H.O. (high-output) 24-valve Cummins ISB (engine code ETH) in 2001; rear disc brakes were added mid-year. This engine is mated to the NV5600 six-speed. Compared to the five-speed NV4500 and four-speed automatic offered behind the 235hp standard-output Cummins, the NV5600 offers additional gear(s) to better keep the engine in its powerband, especially when towing. This trans is nearly bulletproof, even when subjected to high horsepower. (For drag-racing applications, a more-expensive-to-modify auto-trans setup would be used.)

Diesel Dynamics purchased a 36,000-mile '01 1/2 Quad Cab longbed 4x4 for $20,000. Baseline performance numbers were promptly generated on the company's specially constructed Dynojet chassis dyno.

Extensive testing by Diesel Dynamics has spawned package combos that balance more power with tailpipe smoke considerations. While most of these aftermarket upgrades make gains on their own, the overall package output is greater than the sum of the individual parts: These combinations account for each modification's effect on exhaust-gas temperature (EGT). Lowering exhaust heat opens the door for power-making fuel and timing enhancements. Here's an overview of Diesel Dynamics' Cummins ISB H.O. 500hp package:

Here's the Dynojet rear-wheel proof: 218.1 hp stock, 511.5 following a day's worth of bolt-on modifications. Even more impressive are torque numbers: 444.4 lb-ft before, 1,052.2 after. Diesel Dynamics purpose-built this dyno bay by digging a crater into the ground to accommodate the 48-inch drums necessary to handle these torque loads.