More power, more performance, and more economy. That's what we all want for our 4x4s, but it isn't easy to reach these goals without spending a bunch of bucks. However, the three basic bolt-on items that almost always help to free up some ponies are a better air cleaner, hotter spark, and free-flowing exhaust. Since an engine is basically an air pump, letting more air in, igniting all of the fuel, and helping all of the exhaust to get out quickly usually makes for more power, performance, and economy.
Our '79 Jeep Cherokee got the spark and air filter issues addressed in "Power Tune" (May '01), and we were amazed at how much better the beast ran. In fact, our next step was to slap some headers on it to make the rig really run right, but we got into some "emissions-legal" issues, like the local smog laws. It so happens that in Arizona and California (our only registration choices), the federally mandated factory equipment needs to be in place and functioning, or have a smog-certified replacement part installed. However, we couldn't find a single company that had CARB (California Air Resources Board) approved headers, so we were stuck.
Moving to another state or country, or only using the Cherokee off road, seemed a bit excessive, so we delved further. We found that Edelbrock offers a Tubular Exhaust System (T.E.S.), including headers, that is certified for this powertrain, but for '81-'91 models. The differences we knew of between a '79 and later was that the auto tranny was a TH400 and a Quadratrac transfer case in the '79, and a 727 TorqueFlite and NP208 in the '80 and later. Except for the fact that the front driveshaft is on the driver side on the '80 and the passenger side on the '79, they are virtually the same rig. After scoping out the T.E.S. we figured we could get them to fit and pass through the smog check station in just about any state.
We trundled down to Performance Products in Van Nuys, California, to try and make our mess work out right. We first met up with this company on our Ultimate Adventure (Oct. '01) where they were the title sponsor of the trip. After seeing the amount of stuff they carry and the super-sano installation bays, we knew they could handle the project. Here's what we came up with to get some somewhat smog-legal headers for our own rig to keep the smog police at bay.