A V8 like this with a cross-plane firing order has one cylinder firing for every 90 degrees of crankshaft rotation, which means two cylinders are on the power stroke at any given time. As Fenske explains, this contributes to the smooth power delivery V8s are known for.

Firing order reference list

Ford doesn’t even have the same firing order within it’s own engine families in some cases! The Small Block Ford (221-302), Big Block and FE are 1-5-4-2-6-3-7-8. If you rearrange the cylinder numbering to be the same, the small block Chevy and the early small block Ford are the same order.

For the Chevy 350, the HEI Distributor Cap follows the same firing order as the engine: 1-8-4-3-6-5-7-2. On a small block Chevy V8 engine, the distributor cap firing order is in a clockwise rotation.

When the firing order is wrong or delayed, the engine does not run properly. The spark may be delivered to the cylinder when there is no fuel/air mixture or before it is properly compressed. One symptom of an incorrect firing order is the engine does not run. Turning the ignition does not start the engine.

A 4/7-swap cam changes the engine’s firing order, moving the power stroke for cylinder 4 to where 7 used to be, and vice versa.

Ford 302 Firing order is 1-5-4-2-6-3-7-8, the distributor rotates counterclockwise.

Calming down the crankshaft The final benefit for a 4-7 swap is addressing torsional vibration issues with the crankshaft and main bearings. Again, it’s a matter of transferring the loads but there may be a benefit to keeping standard GM firing order in certain applications, like NASCAR.

The most important thing to remember is that the firing order must follow the same pattern as the engine. The Chevy 350 firing order is 1-8-4-3-6-5-7-2. That means next to the number one spark plug wire will be the number 8 spark plug wire, the number 4 and so on in a clockwise rotation.

where should the distributor rotor point? The rotor button should be pointing to the number 1 position on the distributor cap when the number 1 piston is at top dead center (on the compression stroke). The pistons come up two times during the combustion cycle.

Most GM V8 engines (including the 327) had the 1-8-4-3-6-5-7-2 firing order.

Firing Order: 1, 8, 4, 3, 6, 5, 7, 2.

If the manual gives the firing order as 1, 3, 2, 4 and the rotor moves clockwise, connect cylinder three to the distributor terminal immediately clockwise of the number one terminal. Compare the spark plug wires to the manual’s firing order and make sure each wire is attached to the correct distributor terminal.