How to Install AFE 1-7/8 in. Twisted Steel Long Tube Catted Headers & Connection Pipes (15-17 GT) on your Ford Mustang

CAUTION: Allow time for your vehicle to cool down prior to installation. When working on or under your vehicle proceed with caution. Exhaust systems reach high temperatures and may cause serious burns. Wear protective safety equipment; eye goggles and gloves to ensure a safe installation. aFe recommends professional installation on our products.

Step 1: (Read instructions prior to installation) Secure vehicle on jack stands (refer to your own er’s manual for specified jack stand positions.

Step 2: Disconnect the battery.

Step 3: Remove air box.

Step 4: Loosen the muffler clamps on the OE exhaust system and remove exhaust system.

Step 5: Un-plug O2 sensors.

Step 6: Remove starter wire cap and wires from starter and then remove starter.

Step 7: Secure motor with a Jack, Remove the right side motor mount and ground wire.

Step 8: Raise the motor slightly with a jack.

Step 9: Remove the nuts on the right side manifold and remove the manifold and converter pipe.

Step 10: Remove the top (x3) studs on the top rear of the head and the (x1) rear stud on the bottom of the head.

Step 11: With the right side manifold out, remove the O2 sensor wire lead from its loom and from the back of the cyl head so it will reach the new position on the header collector.

Step 12: Install the Right side aFe power header using the original exhaust manifold gasket and (x4) nuts and the 10mm bolts provided where the studs were removed (the original exhaust manifold gasket can be re-used if not damaged replace if necessary) tighten the (x4) header nuts and 10mm bolts starting in the middle and working your way to the outside nuts.

Step 13: Reinstall the right side motor mount and ground cable.

Step 14: Reinstall the starter and cables.

Step 15: Reinstall the right side primary O2 sensor on right side header.

Step 16: Mark and remove steering shaft from rack from the top side of the universal joint.

Step 17: Remove the nuts on the left side manifold and remove the manifold and converter pipe.

Step 18: Remove the second (x1) stud on top front and, (x1) stud on the top rear of the head.
Remove the (x2) studs from the bottom rear of the head.

Step 19: Install the Left side aFe power header using the original exhaust manifold gasket and (x4) nuts and the 10mm bolts provided where the studs were removed (the original exhaust manifold gasket can be re-used if not damaged replace if necessary) tighten the (x4) header nuts and 10mm bolts starting in the middle and working your way to the outside nuts.

Step 20: Reconnect steering shaft.

Step 21: Reinstall the Left side primary O2 sensor on Left side header.

Step 22: Install the band clamps on the right and left converter pipes and slip on the converter pipes to the headers but do not tighten the band clamps yet.

Step 23: Install the secondary O2 sensors on the converter pipes.

Step 24: Install the extension pipes to the converter pipesbut do not tighten the band clamps yet.

Step 25: Re-install exhaust system allign all parts and tighten all band clamps.

Step 26: Reinstall the air box.

Step 27: Reconnect battery.

Step 28: Congratulations, Your system is now complete and fully installed! It is recommended to re-tighten all clamps and bolts after 50-100 miles.