Ali Mansour
Brand Manager, 4WD & Sport Utility
Terrible aerodynamics, a high center of gravity, and more weight in aftermarket accessories than a four-door Civic could safely transport. If that sounds like an accurate description of your Jeep, don’t worry, you’re not alone. We’ve been working on our ’04 Jeep Wrangler Unlimited for a few months now, and the modifications are starting to take its toll on the performance and fuel economy. If we’re being honest (which we always are), the Jeep never delivered great fuel economy in stock form anyway.
Shortly after we installed our new suspension system a few months back, we regeared the axles with 4.88 gears. This helped put the LJ back in the powerband with the 35-inch Toyo mud-terrains, but we wouldn’t call the Wrangler overly spritely. We had outfitted the Jeep with an inexpensive stubby muffler around the same time we installed the suspension. The resulting sound was somewhere between a high-powered vacuum cleaner and a drunken goat, depending on the rpm level. After our last highway trip, we were over the drone and wanted to get something better.
We had already been on the search for a few other performance upgrades and ended up landing at Banks Power. We’ve had good luck with the company’s products in the past and saw that the Stinger System included exactly what we were looking for (exhaust, intake, and programmer). After a few hours wrenching one afternoon, we were able to go test out the new wares.
The first thing we noticed was the annoying exhaust tune was replaced by a throatier and less boy-racer note. The cold-air intake was also more noticeable in both an audible sense and seat-of-the-pants feel. As for the programmer, if you are willing to run the higher octane settings, you will notice an even bigger difference. We’re frugal, so we stuck with the lower-octane tune. With almost 150,000 miles on the odometer, we’ve had a few check engine lights pop up, so it’s been nice to have the on-board scan tool. There are a few other features the programmer offers, but you don’t get as much out of it as you would on the ’07-newer Wrangler platforms.
We used to be especially skeptical about gas engine tuners. Thankfully, newer gas-powered autos can finally get legitimate results out of the handheld programmers. The Banks Automind Programmer gave our ’04 LJ four pre-programmed settings. We’ve cycled through each and found the most noticeable by far is the Super Sport 91. Obviously, this requires a higher octane (93 is actually available where we are on the East Coast, but 91 was the only option). After a few tanks on the high-octane setting, we dialed it back to Sport 87. Ultimately, the performance gains were not enough in the higher settings to warrant the higher price of fuel. It takes only a few minutes to cycle through tunes, so we can quickly swap between.
In terms of power, we wish we could have put the Jeep on a dynometer for before and after results. Can you feel a difference? Absolutely. Is it night and day? Not exactly. Fuel economy has gone up by about 1.1 miles per gallon, according to our hand-calculated figures. We’re guilty of a heavy right foot, so gains could possibly be a little better if we lightened up on the skinny pedal. Ultimately, performance parts are not cheap, regardless of what you drive, but for the quality, fit, and results, we say the Banks Stinger System was well worth the investment.
Due to the location of the 4.0L’s intake, it’s hard to call any stock or aftermarket system a true cold-air intake. The Poison Spyder hood louvers we have installed does help expel some of the under-hood heat, so we are slightly better off than average. The Banks intake ducting is designed to increase flow by optimizing the shape of the intake tube, as well as providing a large cone-style air filter. We like that the intake opening is pointed towards the inner fender, which will lessen the likelihood of an accidental aqua ingestion. Only taking around 15 minutes to install, it was one of the cleanest and easiest upgrades we’ve done in while.
Included with the Banks cold-air intake is a serviceable K&N air filter. We’ve gone on enough trail rides to learn that a serviceable air filter is money well spent. Typically, we’ll wash ours after a long-weekend outing or at each oil change if we’ve been sticking to less dust-filled terrain.
After our suspension install, our Wrangler needed a new cat-back exhaust system due to clearance issues with the stock parts. We’ve used the Banks Monster muffler in the past and liked the fact that it produced a decent sound, without an overly obnoxious drone. The kit includes a muffler, tailpipe sections, and polished stainless steel tip. We’ve actually run this kit without the rear section of the pipe before and had it dump just after the rear axle. The advantage to this is that it clears the suspension components on lifted rigs more easily and you don’t have a tail pipe sticking under the frame just asking to be crushed on the trail. Just as Banks engineered the intake for more flow—measured in cubic feet per minute (cfm)—the 21⁄2-inch stainless exhaust system is designed to expel air more rapidly. Banks measures this as a 140 percent cfm improvement in flow over stock.
