How many camshafts does a car have?
The number varies with the engine design. Most passenger cars use 1, 2, or 4 camshafts, with the exact count determined by whether the engine uses a single-overhead cam (SOHC), double-overhead cam (DOHC), or a pushrod (OHV) layout, and by the cylinder configuration.
In this article, we explain how camshafts are counted and what the typical counts look like for common engine types, including inline engines and V configurations, so you can understand what you might see under the hood.
Camshaft layouts and what they imply
Valvetrain designs determine how many camshafts are used to operate the engine’s valves. In general, one camshaft per engine or per bank is used in SOHC and OHV setups, while DOHC designs use a pair of camshafts per bank. The count scales with the number of cylinder banks in a V-type engine or with inline configurations.
Common counts by engine layout
Below is a concise guide to typical camshaft counts you’ll encounter in modern production cars.
- One camshaft (1): Single-overhead cam (SOHC) configurations and traditional pushrod (OHV) engines with a single camshaft in the engine block or head. This layout keeps the valve train relatively simple and compact.
- Two camshafts (2): Double-overhead cam (DOHC) configurations used on most modern inline-4 and inline-6 engines. Each camshaft operates either the intake or exhaust valves for all cylinders in the row or bank.
- Four camshafts (4): DOHC configurations on V-series engines (V6, V8, etc.) where there are two camshafts per bank, totaling four. This is common in many contemporary performance and luxury vehicles.
In ordinary production cars, most engines fall into one of these three categories. If you’re curious about a specific model, the engine code or service manual will confirm the exact camshaft count.
Exceptions and what’s on the horizon
Beyond the standard arrangements, there are rare or experimental approaches. Some prototypes and concept vehicles explore camless valve actuation, which uses electronic or hydraulic control to operate valves without a traditional camshaft. There have also been historical or niche designs described as three-cam or other non-standard setups, but these are not common in today’s mass-market cars.
As of the 2020s and into the 2020s, camless systems remain largely experimental or limited to specialty applications, while mainstream production sticks with 1, 2, or 4 camshafts based on the engine’s architecture.
Summary
In short, there is no single number for how many camshafts a car has. It depends on the engine design: 1 camshaft for SOHC or OHV, 2 for DOHC inline engines, or 4 for DOHC V engines. Rare or experimental designs may deviate from these counts, but they are not common in today’s vehicles. When in doubt, check the engine configuration of the specific car to determine the exact camshaft count.
Do all cars have two camshafts?
A SOHC engine has one camshaft per bank of cylinders, therefore a straight engine has a total of one camshaft and a V engine or flat engine has a total of two camshafts (one for each cylinder bank).
How many camshafts does a V-6 have?
A V6 engine can have either two camshafts (for a Single Overhead Cam, or SOHC, design) or four camshafts (for a Double Overhead Cam, or DOHC, design). In a V6, two cylinder banks are arranged in a "V" shape, so a SOHC engine has one camshaft for each bank, totaling two, while a DOHC engine has two camshafts per bank, for a total of four.
- Single Overhead Cam (SOHC): A V6 with a SOHC setup has one camshaft per cylinder head (or bank), for a total of two camshafts.
- Double Overhead Cam (DOHC): A V6 with a DOHC setup has two camshafts per cylinder head (or bank), for a total of four camshafts. This is often referred to as a "quad-cam" engine.
Is replacing a camshaft a big job?
While experienced DIYers may tackle minor car repairs, camshaft replacement is complex and typically requires removing or dismantling the upper portion of the engine. This usually involves specialized tools, precise timing adjustments, and extensive mechanical knowledge.
How many camshafts are in a car?
A car engine typically has one or two camshafts, depending on its configuration, with a single overhead cam (SOHC) engine having one camshaft per cylinder bank and a dual overhead cam (DOHC) engine having two. Inline engines have one cam per head, while V or flat engines may have one or two per head, leading to a total of two for SOHC and four for DOHC designs. Older or less common overhead-valve (OHV) engines have a single camshaft located in the engine block, not the cylinder head.
SOHC (Single Overhead Cam)
- Inline engine (e.g., inline-4, inline-6): One camshaft for the entire engine.
- V engine (e.g., V6, V8): One camshaft per cylinder bank, totaling two camshafts.
DOHC (Dual Overhead Cam)
- Inline engine (e.g., inline-4, inline-6): Two camshafts total (one for intake valves, one for exhaust valves).
- V engine (e.g., V6, V8): Two camshafts per cylinder bank, totaling four camshafts.
- Flat engine (e.g., flat-4, flat-6): Similar to V engines, a DOHC flat engine has two camshafts per bank for a total of four.
OHV (Overhead Valve)
- Engine type: Also known as pushrod engines, these have a single camshaft located in the engine block that operates the valves through a series of pushrods and rocker arms.
- Commonality: Less common in modern cars but found in some trucks and SUVs.
