What is the firing order of a Chevrolet LS V8 engine?

The Chevrolet LS V8’s firing order is 1-8-7-2-6-5-4-3. This sequence tells the engine-control system or ignition system when each cylinder should fire during the four-stroke cycle. LS engines use coil-near-plug or coil-on-plug ignition, so the order is programmed and wired without a traditional distributor cap on most applications.

The pattern differs from the older Chevrolet small-block V8 firing order, 1-8-4-3-6-5-7-2. General Motors changed the LS sequence partly through a 4-7 firing-order swap, helping distribute combustion events more evenly along the crankshaft and improving the engine’s refinement and cylinder-loading characteristics.

Cylinder numbering is another frequent source of mistakes. On conventional rear-wheel-drive LS layouts, cylinders 1-3-5-7 are on the driver’s side and 2-4-6-8 are on the passenger’s side. The firing order is not the same thing as the physical cylinder-numbering pattern, and special applications or custom camshafts can require checking the exact engine specification.