Today's diesel truck war between the Big Three is reminiscent of the muscle car era. Each company is doing everything it can to build a more powerful truck. As the trucks become more and more powerful, the aftermarket continues to respond by bringing out the incredible potential of these trucks that has even the hard-core muscle car guys scratching their heads.
| Taking an integrated approach to the entire matter of tuning a diesel truck for performance is a rare and good idea. Accurate and repeatable dyno testing is the key to finding out if parts and combinations of parts really work as billed.
On a recent trip to RUV Motorsports in Ontario, California, we followed along as the crew at RUV completed a total buildup of a Dodge Ram with the venerable Cummins engine. The buildup included a full transmission build, intake, exhaust system, module, and turbo upgrades.
The test vehicle for this buildup was an '05 Dodge Ram 2500 with the Cummins diesel. The truck had approximately 15,000 miles on it, and the owner was ready for more performance and economy. The truck is used as a daily driver with weekend tow duties, so it needed to be super reliable along with offering vastly improved performance.
According to RUV, the weak point in the Dodge platform is the transmission. When power output exceeds 350 rear-wheel horsepower, the stock transmission tends to have a short lifespan without the proper upgrades. The first thing the crew at RUV did was remove the transmission. They installed a BD billet torque converter, BD valve body, hardened input shaft, upgraded clutches and bands, and then finished the upgrade off with a larger-capacity transmission pan from PML.
With the transmission installed, RUV strapped the Dodge down to the in-house Mustang Chassis Dyno for some real-world, rear-wheel baseline power numbers (all dyno runs were backed up for consistency). In stock form, the truck produced 270.5 hp and 524.9 lb-ft of torque.
With initial testing out of the way, RUV pulled out the new parts that were to be installed on the truck. An AFE Stage 2 intake system, Gibson dual-exhaust system, BD power programmer, and BD turbo upgrade were laid out, and the RUV employees got to work installing and dynoing each part.
First, the AFE Stage 2 intake system was installed. AFE's stage 2 intake system features a massive filter and tube system that completely replaces the factory intake system. With the AFE Stage 2 intake system installed on the otherwise stock truck, it produced 291.3 hp and 539.5 lb-ft of torque for an increase of 20.8 hp and 6.5 lb-ft of torque.
With the AFE intake installed and producing promising numbers, the crew at RUV began installing the Gibson exhaust system. The Gibson system is a dual-exhaust system with 4-inch exhaust from the turbo to the muffler and then twin 3-inch exhaust pipes exiting at the rear corners of the truck. With the Gibson system installed on the truck with the AFE intake system, the truck produced 298.9 hp and 539.2 lb-ft of torque for an increase of 7.6 hp and a peak loss of 1.3 lb-ft of torque (it should be noted that the exhaust produced a gain of over 10 lb-ft from just above idle all the way to peak where it lost a slight amount of power).
With the intake and exhaust system installed, RUV plugged the BD programmer into the factory diagnostic port and downloaded the "extreme" power program into the truck. With the Cummins fired up, the big Dodge produced 381.5 hp and 761 lb-ft of torque for an increase of 82.6 hp and 221.8 lb-ft of torque.
With the intake, exhaust, and programmer installed in the truck, the crew at RUV began the process of removing the factory turbo. According to RUV, the factory turbo is a limiting factor in the performance of the Cummins. With the addition of the BD turbo, the truck will have the air it needs to produce big power numbers.
After several hours of removal and installation, the factory turbo was out and the new BD turbo was in. RUV strapped the truck back down to the dyno for a final set of pulls. With the AFE intake, the Gibson exhaust, the BD turbo and programmer installed, the truck produced 397.2 hp and 789.3 lb-ft of torque for an increase of 126.7 hp and 264.4 lb-ft of torque over the stock truck. During the final pulls on the dyno, the crew at RUV found that the truck was running low on fuel pressure and appeared to be starving itself of fuel. According to RUV, the installation of an aftermarket fuel pump will solve the problem and produce an additional 40 hp or so (look for this upgrade in a future article).
At the end of the day it was clear the Cummins had a ton of hidden potential locked up inside. With the right combination of parts, the Cummins can turn from a powerful daily driver to a beast that gives the muscle car guys an extreme case of envy.
DYNO CHART - STOCK TRUCK
RPM - Torque - Horsepower
1,500 - 104 - 35
1,600 - 314 - 105
1,700 - 523 - 174
1,800 - 519 - 181
1,900 - 515 - 187
2,000 - 514 - 196
2,100 - 516 - 206
2,200 - 518 - 216
2,300 - 519 - 228
2,400 - 521 - 240
2,500 - 523 - 250
2,600 - 524 - 260
2,700 - 525 - 270
2,800 - 504 - 269
2,900 - 484 - 267
3,000 - 474 - 266
DYNO CHART - INTAKE
RPM - Torque - Horsepower
1,500 - 98 - 32
1,600 - 287 - 97
1,700 - 479 - 161
1,800 - 492 - 173
1,900 - 505 - 184
2,000 - 513 - 195
2,100 - 514 - 206
2,200 - 515 - 216
2,300 - 520 - 228
2,400 - 525 - 240
2,500 - 531 - 253
2,600 - 535 - 265
2,700 - 540 - 277
2,800 - 539 - 283
2,900 - 538 - 289
3,000 - 538 - 291
DYNO CHART - INTAKE, EXHAUST, MODULE
RPM - Torque - Horsepower
1,300 - 111 - 33
1,400 - 222 - 66
1,500 - 302 - 93
1,600 - 354 - 113
1,700 - 405 - 133
1,800 - 528 - 186
1,900 - 650 - 240
2,000 - 712 - 272
2,100 - 712 - 282
2,200 - 711 - 293
2,300 - 731 - 319
2,400 - 751 - 346
2,500 - 758 - 364
2,600 - 753 - 373
2,700 - 747 - 382
2,800 - 722 - 381
2,900 - 697 - 381
3,000 - 548 - 305
3,100 - 274 - 153
DYNO CHART - INTAKE, EXHAUST, MODULE, TURBO
RPM - Torque - Horsepower
1,500 - 85 - 28
1,600 - 254 - 84
1,700 - 424 - 140
1,800 - 530 - 188
1,900 - 637 - 236
2,000 - 700 - 269
2,100 - 719 - 288
2,200 - 738 - 308
2,300 - 758 - 332
2,400 - 779 - 356
2,500 - 785 - 374
2,600 - 778 - 385
2,700 - 770 - 397
2,800 - 750 - 397
2,900 - 731 - 397
3,000 - 577 - 318
3,100 - 288 - 159
