Ford 5.0L / 5.8L HO V8 Firing Order Diagram 1-3-7-2-6-5-4-8 & Plug Wire Routing

This schematic shows the firing order and spark plug wire routing for the Ford 5.0L and 5.8L HO (High Output) V8 engines. The diagram depicts a top view of the engine with both cylinder banks: cylinders 1 through 4 on one bank and cylinders 5 through 8 on the other. Numbered callouts identify each cylinder position, and the illustration shows how the spark plug wires should be routed from the distributor to each cylinder. A prominent attention note warns that spark plug wires for cylinders 1, 3, 5, and 6 must be routed exactly as shown to prevent crossfire (induction firing between adjacent wires). The document states the firing order as 1-3-7-2-6-5-4-8 and notes that base ignition timing is 10 degrees. A timing scale graphic marked TC (top center), 10, 20, and 30 with an arrow at the 10-degree mark reinforces the base timing specification. A reader can use this document to correctly connect spark plug wires after distributor or wire replacement, verify cylinder numbering, and set base ignition timing on these HO engines.