The sequence 1-8-4-3-6-5-7-2 is the firing order of the Chevrolet small-block V8.
In engine terminology, the firing order is the ignition sequence that determines which cylinder fires first, second, and so on. This particular order has defined GM’s classic two-bank V8 layout for decades, helping balance timing, vibration, and exhaust flow across eight cylinders.
Where this firing order is used
Below is a snapshot of the engines that commonly follow this ignition sequence.
- Chevrolet small-block V8 family, including 265/283/302/327/350/400 cubic-inch variants
- GM-based V8 architectures that trace back to the same overhead-valve design
In practice, this firing order is most closely associated with the Chevrolet small-block family and its GM derivatives, which powered a wide range of cars and trucks since the mid‑20th century.
Mapping the order to the engine’s cylinders
To interpret the sequence on a real engine, it helps to know how Chevrolet numbers its cylinders on a typical small-block V8.
- 1 — Front-right bank, cylinder 1 (closest to the timing cover on the passenger side)
- 8 — Rear-left bank, cylinder 8 (opposite bank, farthest from the timing cover)
- 4 — Rear-right bank, cylinder 4
- 3 — Third-right cylinder, cylinder 3
- 6 — Second-left bank, cylinder 6
- 5 — Front-left bank, cylinder 5 (closest to the timing cover on the driver side)
- 7 — Third-left bank, cylinder 7
- 2 — Second-right bank, cylinder 2
Understanding this mapping helps with timing, distributor orientation, and diagnosing misfires. Always confirm with the exact engine variant’s service manual, as numbering and layouts can vary across GM’s modern recreations or aftermarket builds.
Summary
The 1-8-4-3-6-5-7-2 firing order is the Chevrolet small-block V8’s traditional ignition sequence, used across many GM-era engines. The corresponding cylinder mapping places numbers on each physical cylinder across the two banks, aiding troubleshooting and timing adjustments. When working on a specific engine, verify the exact firing order and cylinder numbering in the factory manual or a trusted service guide.