1997 Jeep TJ - Bolt-On Upgrades - Four Wheeler Magazine

Project Teal-J II, Intro
Project Teal-J II, Part 1
Project Teal-J II, Part 2
Project Teal-J II, Part 3
Project Teal-J II, Part 4
Project Teal-J II, Part 5
Project Teal-J II, Part 6
Project Teal-J II, Part 7
Project Teal-J II, Part 8
Project Teal-J II, Part 9
Project Teal-J II, Part 10
Project Teal-J II, Part 11
Project Teal-J II, Part 12
Project Teal-J II, Part 13
Project Teal-J II, Part 14

What a great idea! Let's drop a rowdy V-8 in between the framerails of our Project Teal-J. On the other hand, let's be realistic. With just a few more than 30,000 miles on our rig, there was no reason to replace the 4.0L inline-six. While the 4.0L has never been known as a powerhouse, it more than likely would be fine for most of our uses--and at its current mileage, it's barely broken in. It is a solid and reliable engine that we don't have to worry about. Also, there's the little matter of time, which we simply don't have much of in these busy days. In the end, our engine plans did a complete 180. There would be no V-8. Instead, we decided to keep the trusty 4.0L, and to add some oomph through the use of parts that bolted on easily. A requirement was that due to our lack of time and shortness of deadlines, all of our parts had to install within a weekend. Additionally, since we were working out of our driveway, there was to be no custom fabrication of any kind involved--always an important blessing.

After browsing through the many options that presented themselves to us, we decided to add power by improving upon the Teal-J's breathing. To make our Jeep inhale more easily, a new throttle body from Rubicon Express was installed, along with a new air intake from AEM. Improving the situation during exhalation is a PaceSetter header and a TFX after-cat exhaust system, also from PaceSetter. A Jet Performance chip that we found in the Performance Products catalog (which has a host of Jeep goodies) was also installed to allow its computer wizardry to release a few hidden horsepower.

In the end, all the parts met our requirements. Installation was easily handled in a lazy weekend of wrenching. Our TJ's 4.0L now breathes easier and produces the increased power and improved throttle response we'd hoped for. Follow along as we show you what is involved in getting more power from your TJ.

The Header

Our first step was to soak all the nuts and bolts we would be removing in JB 80 to help to break the bond between any rusted fasteners and act as a lubricant, making removal easier.
Our first step was to soak all the nuts and bolts we would be removing in JB 80 to help to
Next, we loosened the bolts that attached the header to the block. Some of these are accessible from the top of the engine bay, while others require an approach from the bottom of the vehicle.
Next, we loosened the bolts that attached the header to the block. Some of these are acces
Installing a new header on a TJ is difficult and time consuming because to get the header out, the intake manifold must also come off. To accomplish this, the power-steering pump must be unbolted from the intake manifold. To prepare for this step, we loosened the adjusting pulley so the serpentine belt could be removed.
Installing a new header on a TJ is difficult and time consuming because to get the header

After the belt is off, the power-steering pump assembly can be unbolted from the intake manifold.
After the belt is off, the power-steering pump assembly can be unbolted from the intake ma
The next step is to unplug all the sensors, throttle cable, vacuum hoses, wiring for the fuel injectors and whatever else is attached to the intake manifold. Depressurizing the fuel-injection system also is recommended along with using a special tool to remove the fuel lines. We found that we did not have to do this; instead of fully removing the manifold, we simply rotated it up and over while taking care not to damage the fuel lines. Once that was accomplished, we were able to remove the exhaust manifold.
The next step is to unplug all the sensors, throttle cable, vacuum hoses, wiring for the f
Factory Jeep manifolds are notorious for cracking, so we were glad to replace ours with a new header from PaceSetter. In addition to looking much better, the PaceSetter headers feature mandrel-bent 1 ½-inch tubing and a 2-inch collector to help increase flow and add horsepower.
Factory Jeep manifolds are notorious for cracking, so we were glad to replace ours with a

We like the nice, thick flange that the PaceSetter headers come with. The headers are available in black paint, but we chose the Armor Coat option, which won't discolor or dull and reduces underhood temperature. It also gives the header a nice appearance and resists corrosion. Another important feature of this TJ header is that it is smog-legal in all states.
We like the nice, thick flange that the PaceSetter headers come with. The headers are avai
With the old header out of the way, remove the old gasket material, make sure all mating surfaces are clean, and pop the supplied new gasket into place. Then the header can be installed and the intake manifold put back into position. While it might look simple, expect the header install to require the majority of your install time.
With the old header out of the way, remove the old gasket material, make sure all mating s

The Exhaust

Our headers from PaceSetter came with this nice Y-pipe. It features smooth mandrel bends and the Armor Coat option for protection and durability. It was the next item to go into place.
Our headers from PaceSetter came with this nice Y-pipe. It features smooth mandrel bends a
PaceSetter also has replacement catalytic converters, one of which we planned to use. However, the company does not make a direct replacement for the TJ, but rather a universal piece that would have involved some fabrication to install.
PaceSetter also has replacement catalytic converters, one of which we planned to use. Howe
Since we didn't have a welder or exhaust shop close to us, we decided not to use it.

Our next step was to install a TFX Kat-Back exhaust system, also from PaceSetter Performance Products. The muffler features an aluminized coating to prevent rust and is also designed to increase flow. It simply slides over the catalytic converter and is then clamped into place.
Our next step was to install a TFX Kat-Back exhaust system, also from PaceSetter Performan
The system also comes with 2 ½-inch aluminized, mandrel-bent tubing. The smooth, kink-free bends maximize exhaust flow and add horsepower. It goes up and over the axle and exits out the rear with a chrome-plated tip.
The system also comes with 2 ½-inch aluminized, mandrel-bent tubing. The smooth, ki
A nice feature of the TFK system is that it uses the factory mounts and uses this nice system of easy-to-slide-in mounts that utilizes a washer and cotter pin to be held in place. This is a lot easier than having to monkey-motion a mount with a bend in it through the factory rubber mounts.
A nice feature of the TFK system is that it uses the factory mounts and uses this nice sys

The Throttle Body

Installing our new throttle body from Rubicon Express was very simple. We simply detached all the sensors and linkage from the factory throttle body, removed it, and then installed the new one.
Installing our new throttle body from Rubicon Express was very simple. We simply detached
The Rubicon Express throttle body uses a bigger 62mm bore to increase flow for more power. It fits all Jeep six-cylinder fuel-injected engines from '91-'02. We bolted it back into place on the spacer that came with our AEM Brute Force Intake System. Then it was just a matter of reattaching all the sensors and throttle linkage.
The Rubicon Express throttle body uses a bigger 62mm bore to increase flow for more power.

The Air Intake

Another part we used to increase airflow is the Brute Force Intake System from AEM. One of the first pieces to go on is this aluminum heat shield.
Another part we used to increase airflow is the Brute Force Intake System from AEM. One of
Next comes the mandrel-bent aluminum intake tube that is tuned on a dyno in both length and diameter for maximum power. Ours was powdercoated grey, but a polished tube is also available. It attaches to the throttle body on one side and then the heat shield on the other. Visible in this photo is the CARB EO number that makes it a smog-legal part in all 50 states.
Next comes the mandrel-bent aluminum intake tube that is tuned on a dyno in both length an
The air filter is the final piece to finish off the intake system. It is designed for maximum horsepower by increasing airflow but at the same time is better at filtering. Also important for those that spend lots of time on the trail is that it is cleanable and reusable.
The air filter is the final piece to finish off the intake system. It is designed for maxi

In this finished shot, you can see how the air filter is much bigger than the original factory piece, and the smooth bends of the air intake help to increase airflow and add power.
In this finished shot, you can see how the air filter is much bigger than the original fac

The Chip

While browsing through the Performance Products catalog for power-producing goodies, we came across the JET Power Control Module. We chose a Stage II module that is designed for use on vehicles equipped with headers and performance exhaust systems along with free-flowing intakes. It adds power and improves throttle response by reprogramming the fuel/air mixture and ignition timing for maximum performance. The chip is said to add up to 15 hp and increase low-end torque.
While browsing through the Performance Products catalog for power-producing goodies, we ca
Installing the JET Power Control Module was our favorite part of this exercise because it was so easy to do. We simply located our vehicle's ECU on the firewall, unplugged the black color-coded terminal, attached the module and then plugged the black terminal into it. It took about three minutes.
Installing the JET Power Control Module was our favorite part of this exercise because it
When using the Stage II module, it is also necessary to install a low-temperature thermostat. JET offers this 180-degree unit, which we also got through Performance Products.
When using the Stage II module, it is also necessary to install a low-temperature thermost

SOURCES
Advanced Engine Management Inc. 2205 126th St., Unit A Hawthorne CA 90250	Performance Products Inc. Dept. FW Van Nuys CA 91406
PaceSetter Performance Products P.O. Box 56397, Dept. GMHTP Phoenix AZ 85079-6397	Rubicon Express rubiconexpress.com