How to Install Mopar Big Block Headers
- 1). Raise the vehicle with a jack and place it securely on jack stands. You will need several feet of clearance to install the headers from below so make sure your jack stands are tall enough to provide adequate clearance. The best way to lift the car is with a full size vehicle lift.
- 2). Disconnect the steering linkage with the appropriately-sized socket and move it out of the way. Consult the shop manual for your car for more specific instructions.
- 3). Unbolt and remove the oil dipstick tube and the dipstick. Disconnect the wires that go to the starter and unbolt and remove the starter with a socket. Remove the spark plug wires and use a spark plug wrench to remove the spark plugs.
- 4). Unbolt the original manifolds where they attach to either side of the head. Disconnect the manifolds where they bolt to the exhaust system.
- 5). Unbolt the engine mounts so that the motor can be moved a little to allow the manifolds to be pulled out of the engine bay. Also drop the steering arms by detaching them from the idler arm and steering box so they can be moved to allow for adequate clearance.
- 6). Clean the area where the headers mount with gasket cleaner and degreaser. Scrape off any remains of the old gasket and ensure that the mounting surface is clean and smooth.
- 7). Place a new header gasket on either side of the heads where the headers mount. If necessary, use small pieces of masking tape to hold the gaskets in place while you install the headers.
- 8). Install the new headers from the bottom of the car, moving the engine 2 to 3 inches, as needed, to allow for the proper amount of clearance. You can also place a block of wood under the engine's oil pan and lift the motor with the jack to allow enough clearance. Be careful not to damage the oil pan if this method is used.
- 9). Bolt the headers on with the header bolts but do not tighten the bolts. Bolt the headers to the exhaust pipes. Tighten the bolts to the header manufacturer's recommended settings. Tighten the bolts that fasten the headers to the heads.
- 10
Reinstall the starter, the steering linkage, spark plugs and anything else that was removed. Lower the car to the ground. - 11
Start the engine and allow it to get up to operating temperature. Shut off the engine and, with the headers still warm, re-check the tightness of the bolts and, if necessary, tighten them again with the torque wrench.
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