How to install BBK Chrome Unequal Length Shorty Headers on your 1986-1993 Mustang

Step 1 Make sure engine is cool and disconnect negative battery terminal.

Step 2 Remove the hose clamp at the throttle body, unplug the mass air sensor if so equipped and remove hose assembly for access.

Step 3 Remove air injection tubes from passenger side*(see note).

Step 4 Remove the spark plug wires and the spark plugs.

Step 5 Working from under the vehicle (use caution) remove the nuts connecting the h-pipes to the exhaust manifold and the nuts holding the mufflers to the h-pipe and slide the h-pipe back a few inches for clearance.

Step 6 Remove the stock exhaust manifolds and clean any gasket material from the heads. (Header removal and installation is from the inside of the engine compartment.)

Step 7 Using the gaskets provided start all the new header bolts before tightening the new headers to specs.

Step 8 Reverse previous steps to complete installation.