Last Updated on February 18, 2023 by Leepu Da Maxim
The firing order of a Chevy 350 small-block engine is 1-8-4-3-6-5-7-2. In this order, you can tell that cylinder #1 fires off first. After the first one is done, cylinder #8 takes over, then cylinder #4, and so on until cylinder #2 finishes off the ignition pattern.
- The cylinders on the Chevy 350 are arranged from the front of the engine to the back, starting at the driver’s side
- In the Chevy 350 small-block engine, all the even-numbered cylinders are on the right of the engine, and the odd-numbered cylinders are on the left side
- The firing order is the sequence in which the engine’s cylinders fire, so you have to ensure that the spark plugs are wired in the correct order for proper engine operation
- It is very important to know the firing order of your Chevy 350 to prevent ignition crossfires
What is a firing order?
The firing order refers to a pre-determined sequence in which the ignition system gives a spark to each cylinder. The spark is what ignites the air-gas mixture, and the ignition has to occur in the right pattern for the Chevy 350 to work correctly.
The correct firing order ensures the engine lasts as long as possible. It also minimizes vibrations and keeps the engine balanced. Since the Chevy 350 is a V8 engine, all the cylinders can’t fire simultaneously. There needs to be a specific order to ensure that all cylinders warm-up and sync with each other in a specific way.
Multi-cylinder engines such as the V8 engine have highly-coordinated firing orders for the following reasons:
- To encourage the smooth operation
- Balance the engine
- Minimize vibrations
- Prolong engine fatigue life
- Ensure driver and passenger comfort
When you get the firing order right, you will enjoy a smooth driving experience and a responsive vehicle. If you mess things up, your vehicle will feel uncomfortable with a bumpy ride. Getting the firing order wrong can lead to early engine failure.
Every engine variation has its specific firing order from the manufacturer; for the engine to function at maximum potential, you need to know the firing order.
Why is it important to know the firing order of your Chevy 350?
- To prevent ignition crossfires
Ignition crossfires happen when two adjacent spark plugs fire at each other. When this happens, the magnetic field from the spark fires the next spark plug before its time. This causes the engine to run rough and misfire.
You can prevent an ignition crossfire by crisscrossing the adjacent plug wires to cancel the magnetic induction. Misfires can also happen on engines featuring coil-on-plug ignition systems with an engine module or engine computer controlling the firing order.
In such engines, the crankshaft position sensor sends an input signal to the engine computer to identify which piston is moving up to the center of the compression stroke. This then fires the first spark plug, the next one, and continues according to the firing sequence.
- To ensure the engine functions optimally
The firing order of your Chevy 350 small block engine has to be consistently right. Always ensure that the spark plugs aren’t mixed up because that may cause starting issues with the engine. If the engine starts, it will mostly run in an inferior condition.
Does the High Energy Ignition distributor have a different firing order?
Most small block Chevrolet engines use an HEI distributor to facilitate the transfer of electric energy from the ignition coil to the spark plugs.
The HEI distributor cap has a unique firing order that follows a clockwise rotation for the small block Chevy V8 engines. So long as the wires are connected correctly, it doesn’t matter where the number one position is. For the Chevrolet 350 small block engine, the HEI distributor cap follows the engine’s firing order:1- 8- 4-3-6-5-7-2.
What is the firing order for other Chevy engines?
Older V8 engines use the Chevy small block firing order, which is 1-8-4-3-6-5-7-2. The V8 engines have a cross-plane crankshaft design that is also present in other engines used by GM, Ford, and Chrysler. Ford engineers use a different numbering system for their cylinders, making the firing system appear different, but it is similar to the Chevy 350.
The Chevrolet V8 engine firing order is 1-8-4-3-6-5-7-2 in the small block engines, which include (chevy 265, 302,283,350,400, and 327)
It is also the same in the Chevy V8 big-block engines, including (396,406,427 and 454)
5.3 L engine
You’re probably curious whether the firing order of a Chevy with the 5.3 L engine is the same. The firing order for this type of engine is 1-8-7-2-6-5-4-3. This firing order is different from other Chevrolet cars with small block engine motors and is typical for LS engines.
5.7 L engine
The 5.7L engine has the same firing order as the Chevy SBC 350, which is 1-8-4-3-6-5-7-2.
Chevy LS1 to LS7
The Chevy LS series has a different firing order from other small and big-block V8 engines. Its firing order is 1-8-7-2-6-5-4-3.
These firing orders are for a standard cross-plane crankshaft where the throws are 90 degrees apart and a standard camshaft.
Is it possible to change the firing order?
No, you cannot change the firing order because it is pre-determined in the design and layout of the camshaft and crankshaft relationship.
How can you tell if the firing order is wrong?
If the firing order is wrong or the spark takes longer, you will notice problems with how the engine runs. The most common symptom of an incorrect firing order is the engine refusing to start. If you turn on the ignition and the engine doesn’t run, the chances are that the firing order is wrong.
The firing order ensures the engine stays balanced and has the least possible vibrations. It also helps prevent engine misfires by ensuring power gets to the cylinders correctly. It is important to know the cylinder arrangement in your Chevy and the firing order to ensure everything works correctly and efficiently.