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How to Install PaceSetter Black Long Tube Headers on Your 1996-2004 GT

Installation Time

1 days

American Muscle
Shop Parts in this Guide

Before beginning installation, read and make sure you understand all instructions, and have necessary equipment at hand.

Before working on the vehicle, make sure that it is well supported by jack stands or ramps of sufficient load capacity for the weight of the vehicle. NEVER work on any vehicle which is supported only by its service jack.
1. Disconnect battery. Raise vehicle on lift (preferred), or on jack stands or ramps.
2. Remove air intake tube and air cleaner. Loosen EGR tube at EGR valve. Disconnect air fittings on top of exhaust manifolds if equipped. Remove dipstick and dipstick tube.
3. Disconnect all four O2 sensors. Unbolt H-pipe from exhaust system, slide exhaust to rear. Unbolt H-pipe from exhaust manifolds and remove.
4. Disconnect steering shaft from steering rack and swing shaft down and out of the way.
5. Support engine and remove motor mounts and motor mount brackets.
6. Disconnect EGR tube from exhaust manifold. Remove exhaust manifolds and manifold studs. Remove starter.
7. Clean manifold gasket surfaces of cylinder heads. Reinstall an original stud into the forward top hole of each head. Install to full depth but do not tighten.
8. Remove bolts from transmission mount to transmission and push trans to the left and slide right header into position. Temporarily hang header on the forward stud. Reinstall right motor mount and bracket onto block. Do not bolt to crossmember yet.
9. Push trans to the right side and slide left header in place. Hang header on the forward stud. Swing steering shaft back into place but do not bolt up yet. Install the dipstick tube through the header and into the block.
Reinstall the motor mount and bracket onto the block. Do not bolt to crossmember yet.
10. Apply a high temperature, O2 sensor safe gasket sealer such as Permatex Ultra-Copper on one header gasket and bolt up left header with new header bolts. Remove temporary stud and replace with header bolt, but do not tighten header bolts yet.
11. Apply the high temperature gasket sealer to the remaining header gasket and bolt up right side header. Install the remaining header bolts, remove the temporary stud, replace with a header bolt. Do not tighten the bolts yet.
12. Reinstall motor mount lower nuts and transmission mount bolts. Bolt up steering shaft. Install EGR tube fitting onto header fitting, but do not tighten yet.
13. Confirm alignment of collectors and snug header bolts. Torque header bolts from center out. Final torque should be 18 ft.lbs. Tighten lower EGR fitting. Reinstall starter.
14. Loosely install O2 sensors in fittings in collectors and measure amount of wire extension necessary. Remove O2 sensors and extend wires per enclosed instructions. Install O2 sensors.
15. Reinstall air intake tube and air cleaner. Tighten upper EGR fitting. Reconnect air fittings as equipped.

Header installation is complete, ready for Y-pipe/exhaust system.
Remove jack stands and lower vehicle. Re-connect battery and start engine.
Check for exhaust leaks, rattles, clearance problems. Correct if necessary.

There may be some lubricant left in the tubes from the mandrel bending process. You may smell this lubricant burning off for the first few days of using your new headers. This is normal and will cause no harm and will disappear. After a few days of operation, check all fasteners. Retorque as necessary.

This guide applies to Vehicle years: 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004 and Submodels: Bullitt, GT