1. Raise vehicle, the higher the better.
2. Liberally spray all exhaust-related fasteners with rust penetrant and allow to soak.
3. Although it is not absolutely necessary it will be much easier to access the manifolds and headers by removing the vehicles battery and air cleaner housing.
4. Battery – Disconnect negative if leaving battery in vehicle.
5. Air cleaner housing – loosen and remove the air tube, the air cleaner top is held into place by tension clips, using a screwdriver flip those back and remove the top, and the filter. There are (3) bolts that fasten the housing to the fender well (1) One inside (1) one outside, and one underneath the plastic inlet house. On the plastic elbow there is a plastic ribbed push lock, using a screwdriver, carefully back it out and remove housing.
6. Disconnect the oxygen sensor lead wires where they plug into the wiring looms beside the transmission. They don’t disconnect at the sensor itself!
   Warning: Failure to disconnect the oxygen sensors from the looms before removing the sensor can cause them to “wind up” and fray the wiring at the sensor end. Any damage done to the oxygen sensor wiring can cause the sensor to send false signals back to the on-board computer, which can ruin the computer’s ability to accurately maintain the correct air-fuel ratio.
7. Disconnect the stock connector pipes from the bottom of the exhaust manifolds.
8. Cut the inlet pipe approximately 1” in front of the catalytic converter.
9. Remove both of the stock exhaust manifolds.
10. Clean ALL TRACES of carbon off of the cylinder head exhaust port surfaces. MOST HEADER GASKET SEALING PROBLEMS OCCUR BECAUSE OF CARBON DEPOSITS THAT WERE LEFT ON THE SEALING SURFACES.

Note: While under the vehicle, inspect the starter wiring for embrittlement and make sure it is secured away from any source of exhaust heat.

Re-Assembly

11. Staring from above the engine compartment on the driver side, corkscrew the header into place. Install the gasket and put header up into position.
12. Install all of the bolts and washers on the driver side and tighten them at this time.

Note: Before installing the passenger side header take note of the two sheet metal screws retaining the heat shield to the firewall. These screws have long sharp points and can interfere with the header fitment. If so trim approximately ¼ “ off the screw tips for clearance.

13. Starting from above the engine compartment on the passenger side, aim the header towards the front exhaust port and slowly work the header into place.
14. Install all of the bolts and washers on the passenger side and tighten them at this time.

Y-Pipe installation

15. Assemble the Y-pipe parts on the floor underneath the truck so you can see what goes where.
16. Attach the driver side front section to the bottom of the driver side header LOOSELY using gaskets and hardware provided in the kit.
17. Attach the y-pipe to the passenger side header loosely using the gaskets and hardware provided.
18. Insert the intermediate pipe over the left-hand connector pipe and into the y-pipe (this joint is slip fitted on both ends) align the components and tighten the bolts on the header collectors at this time.
19. Bolt the 3” to 2 ½” reducer flange to the end of the y-pipe using the gaskets and hardware. Index the inlet pipe of the catalytic converter into the outlet of the reducer flange and weld this connection.
20. Re-install oxygen sensors and then plug wiring back into harnesses.
21. Re-install negative battery cable and air inlet hose.
22. Re-check tension on ALL fasteners.

Cosmetic tip: Wipe headers down with rubbing alcohol and a clean, dry cloth BEFORE firing the engine for the first time. This will eliminate ugly yellow spots that occur when skin oils and/or engine compartment grime are left on the headers and then heat is applied.

23. Start engine and check system for leaks.

It is critical that the bolts be checked for tightness after the first 20 minutes of operation.

Header Bolts “Stretch” due to exhaust heat! The header bolts should be inspected from time to time to prevent gasket leaks. It’s suggested that you check them after the first full day of operation, and then check them again every couple of months for the first year of operation. The bolts will reach their maximum stretch length after about a year, but check them every 6 months anyway. The Mopar Performance header gaskets are made from a special material that will take more heat than cast iron itself, so the only way a gasket can be “blown” is from the bolts getting loose and being left loose.

The vehicle may not run a bunch stronger immediately, and may not idle properly at first. This is because you’ve made a dramatic change in the way it breathes, and the on-board computer must have some time to adjust to the changes. The computer frequently takes between 500 and 700 miles to dial itself in, so please be patient while your vehicle “learns” to take maximum advantage of the changes you’ve made.

Final Note: You may notice a “burning rubber” smell when the vehicle is first fired up, and immediately after the first long hard full-throttle pulls you do. This is caused by the special-composition header gaskets “burning in” and taking set. However, Please fell free to check and double-check that no hoses or rubber components are being incinerated!

Questions/comments/worries call Mopar performance tech line (248) 969-1690