Have you ever stopped to think about how much dyno-testing has been done in this country? Manufacturers test their products against the competition and against themselves, and search for the best possible results. But, what happens when you start combining some of these products together? Your cold-air intake system does not live alone in a bubble, and your results may vary when you've also installed an exhaust system, added a power programmer, and more.
It's a big mistake, which the uninitiated often make, to simply add up the horsepower and torque claims of the manufacturers' individual products and take that as a definite result. The savvy diesel enthusiast knows that when you combine different products the results are not always what you would expect. Sometimes, the combination is simply a dud, while other times the mixture of products results in gains that no one expected. The problem with this scenario is finding a shop that has dyno-tested a variety of products and has both before and after test results.
While there are not all that many shops around that dyno test everything they sell, there are a few. We hooked up with a real winner when we consulted RUV Motorsports in Ontario, California. Using a Mustang dynomometer, the shop is able to verify both the baseline and the end results with a repeatability that would make a NASCAR team proud. Owner Jeremy Lachenmyer is a stickler for results. He doesn't install anything at his shop without first dyno-testing it and has often guided customers away from the product they thought they wanted to buy with something completely different (and sometimes less expensive) based on test results.
We asked Jeremy to sift through the more than 10,000 dyno tests he's performed and pick out some of the best combinations of parts he's seen. It took some arm-twisting and a weekend of searching through files, but Jeremy came through and supplied us with some real eye-opening results. Keep in mind that some of these combos require a transmission upgrade and none of them-especially the '01-'03 Chevy Duramax-can be used at the higher settings when towing. You must tune them down. You don't have to turn them all the way off, but the lower settings are all you can use when loading your truck down.
Each of these combinations is real and was tested on a real-world truck. Each is a daily driver and also does tow duty with loads ranging from 8,000 to 15,000 pounds. Virtually all can still achieve 20 mpg when unloaded under light throttle use, although the 7.3L Ford is more like 14 mpg on a good day. Peruse these dyno-proven power packages and it just might give you some ideas for your own truck.