We used a late-model Dodge...
We used a late-model Dodge as our test mule. While the stock Dodge intake system wasn't bad, it could be better served with a more dynamic air filter and some added airflow.
Everyone wants instant results when it comes to performance, and the most economical way to achieve it is by increasing the airflow coming into the engine. If that's all you ever do, you'll be a happy camper. Obviously, you'll want to do the same with the air exiting the engine too, but if money is tight, start with the intake system.
Aftermarket air intake systems have been around for a long while, and their benefits have been proven. To give you an idea of how really simple it is to bump up your performance and perhaps add a few more miles per gallon using an aftermarket intake, we followed along as Dependable Off-Road installed a True Flow XDi Extreme Duty intake on a late-model Dodge diesel.
Dependable Off-Road owner Steve Elliott went over all the possibilities, and in the end the True Flow system won out over an array of others. "On this application we removed the restrictive resonators on the stock engine and replaced them with smooth mandrel-bent tubing," says Elliott. "We replaced the stock air box with a high-flow canister. We changed the direction of the air filter so that the air flows from the inside out." Elliott calls it inverted airflow technology. According to him, this can increase the airflow more than 50 percent, which results in more horsepower and torque.
Here's a brief look at our installation. Keep in mind that certain new vehicle warranties might restrict any type of aftermarket performance upgrade, so if you're concerned, check with your dealership before you begin.
 The reason the True Flow system...  The reason the True Flow system doesn't look like anything else you've seen is because the air flows from inside the filter outward. The kit comes with complete instructions, and it can be installed with common handtools. |  The first thing we noticed...  The first thing we noticed on the stock intake was a really dirty filter, which most likely would have robbed some performance from the engine. The foam air filter of the new XDi system is easily cleaned and offers a lifetime warranty. |  The canister of the XDi fits...  The canister of the XDi fits where the stock intake housing was located. |
 The design of the intake makes...  The design of the intake makes it easy to snap the factory sensor clip in place. |  All the factory emission lines...  All the factory emission lines hook right up to the XDi so your truck will never know something has been replaced. |  Here's a look at the finished...  Here's a look at the finished product. All it took was 20 minutes to bring some life back into the diesel thanks to improved airflow. |