The correct wiring pattern of a Ford 351 engine distributor is essential for proper ignition. The wires must be directed from the distributor contact posts to their respective spark plugs without overlay, which can cause cross-firing. Cross-firing results from the magnetic field produced when electrical ignition current passes from one distributor wire to another, causing two cylinders to fire at the same time. You can wire a Ford 351 distributor with the proper tools and materials.
Place wheel chocks under both sides of the rear tires.
Set the shift lever in the "Park" position. If the vehicle is equipped with a standard transmission, place the shift lever in first gear. Apply the emergency brake and remove the keys from the ignition.
Raise the hood and place a fender cover where you are working. Remove the negative battery cable using an adjustable wrench to loosen the clamp nut. Remove the clamp from the battery post with a battery post clamp puller.
Remove the air cleaner from the engine by turning the wing nut located at the top of the air cleaner shroud counterclockwise by hand. Disconnect the PCV valve hose on the side of the air cleaner by pulling it straight off by hand.
Locate the distributor which is front and center on the engine. Its cap has eight posts surrounding it with a single post in the middle.
Locate the firing order on the intake manifold. It will read "1 - 3 - 7 - 2 - 6 - 5 - 4 - 8." These numbers correspond to posts on the distributor. As you face the front of the vehicle, cylinder numbers "1", "2", "3" and "4" are on your left and "5", "6", "7" and "8" are on the right, in that order.
Lay the ignition wires out and arrange them by length. Select one of the shortest wires and snap the taller booted connection end onto the Number One spark plug until fully seated. The other end of the wire has a smaller boot
Check the top of the distributor cap for the Number One position which is at the rear of the cap and slightly toward the driver side.
Place the smaller booted connection into the Number One post socket making sure the contact is fully seated. The boot must be placed completely over the post.
Insert the wire into the first wire harness slot on the valve cover above the cylinder head. The harness keeps the wires orderly and separated from one another to prevent cross-firing.
Check the top of the cap for an arrow. The direction in which the arrow points indicates the direction the ignition rotor turns inside the distributor. All the other wires follow this direction from the Number One wire according to the firing order.
Connect the next appropriate length wire onto the Number Three spark plug placing it in the third slot of the wire loom. Connect the short booted end next to the Number One in proper succession according to the arrow direction.
Connect the next wire from the distributor post to the Number Seven spark plug, the next to Number Two, the next to Number Six, the next to Number Five, the next to Number Four and finally the last to Number Eight.
Connect the coil wire from the center post of the distributor to the single post on the coil. Both ends of this wire have small boots. Make sure both end connections are seated and the boots pulled over the posts.
Check the wiring harnesses to make sure all the wiring is connected properly with no overlapping.
Connect the negative battery cable and tighten the post clamp nut with the adjustable wrench. Account for all tools and materials used and close the hood. Remove the wheel chocks.
