In this article, we would be answering a couple of Q&A like what does a camshaft do? We came up with this article with the sole purpose of helping you understand the camshaft better.
First, you need to understand that the camshaft is one of the most important parts of an engine as it is responsible for opening the valves in your car’s engine.
Additionally, the camshaft has other functions, but it mainly depends on the design of your engine. Understanding what a camshaft does would require you to study how it does it and why it’s important.
But first, let’s understand the meaning of a camshaft, and then from there, we can address other questions.
Table of Contents
What is a camshaft?
A camshaft is a rotating object made with solid metal that comprises two main parts: the cams and the shaft.
And the main function of a camshaft is to open and close the intake and exhaust valves allowing the mixture of fuel and air, and gas to come out of the cylinder.
Camshafts function by converting rotational motion to oscillatory or reciprocal motion. Common applications of camshafts are in internal combustion engines and mechanically controlled ignition systems.
Located beneath the engine of a car, camshafts are fitted in so many configurations, with each configuration operating slightly differently.
Depending on how the motor of your car is engineered, but there are two standard configurations for a camshaft.
The camshaft can either be configured in the cylinder head above the valve, or in the engine block itself. A camshaft has lobes attached to all its valve.
And the function of these lobes is that they create some sort of pressure on the valves such that as they rotate, it forces them to open. The shape of these lobes can affect the performance of a car’s engine at different speeds.
What does a Camshaft do Silverado: the Benefits of the Camshafts
Now, let’s look at the functions of a camshaft. But to understand what a camshaft does, first, you need to understand the operation mechanism of the highly configured camshaft, which is fairly straightforward.
Converts rotational motor to oscillatory motion
The camshaft and crankshaft are connected directly by gear or indirectly by a pulley system. So, when the crankshaft rotates, the camshaft converts that rotational motion to oscillatory motion.
For example, consider a two-cycle engine, the camshaft, and the crankshaft rotates at the same speed.
But in a four-cycle engine, the camshaft and the crankshaft do not rotate at the same speed as the camshaft rotates at half the speed of the crankshaft.
Control pistons
Another function of the camshaft is that it controls the piston movement. The piston of an engine moves as a result of the oscillatory motion from the camshaft.
The oscillatory motion of the piston also known as the Otto Cycle is important for the functioning of an internal combustion gasoline engine.
The Otto Cycle engine works starting from an intake stroke to a compression stroke, to a power stroke, and finally to an exhaust stroke.
As such, without the camshaft in internal combustion engines, the movement of the piston which enables continual production of energy from the engine for the proper functioning of the car will not be possible.
Fuel and air mixture
As the camshaft rotates, it opens a valve and closes others letting fuel and air into the combustion chamber.
In the combustion chamber, a spark is produced, which ignites the fuel and air creating a blast that propels the piston keeping the engine running.
Valve timing
One of the most common purposes of a camshaft is valve timing. Timing is important!
The valve has to be opened for the intake of fuel and air, and exhaust gas at the right time to maximize the power of the engine. The slightest discrepancy in valve timing can result in inefficient engine performance.
Performance tuning
The importance of valve timing cannot be emphasized enough, because it plays a vital role in the performance tuning of a car.
However, the dimension and timing of the cams can be altered in such a way that it is able to open the valve in a timely manner to ensure optimal performance. A properly tuned and timed camshaft could mean a microsecond difference.
Also, the camshaft lift also comes into the picture when talking about performance tuning. In other words, the more the lift, the more the flow, which in turn gives you more power.
The general engine design and reliability put a limit to the amount of lift.
Comp Camshaft Specs: What you Need on a Camshaft
No company defines automobile performance better than Comp Cams. Founded in 1976, Comp Cams is the undisputed leader in camshaft technology. The importance of the right camshaft is increased torque, horsepower, and fuel economy. There are four main types of camshafts:
- Hydraulic flat tappet camshaft: For those on a strict budget, this type of camshaft is recommendable for you as it is the least expensive.
- Solid flat tappet camshaft: This is another category of the camshaft that makes more power than the hydraulic flat tappet and is still low in cost.
- Hydraulic roller camshaft: Another category of camshafts is the hydraulic roller camshaft with an outstanding power second to none, although more expensive.
Hydraulic roller camshafts are the easiest to maintain.
- Mechanical roller camshaft: Lastly, mechanical roller camshafts make the most power out of all the camshafts you’d find in the Comp Cams catalog.
It features more high lift area, quicker ramp speeds, and offers the ability to achieve more horsepower and torque.
Comp Cams makes use of a lot of terminologies, which can be pretty confusing. Here is the meaning of some of the most common terminologies.
- Lift: In simple terms, the lift is the distance in inches that the valve opens up and down.
Lift is of three common types: net valve lift, gross valve lift, and cam lift. The lift of a camshaft refers to the maximum distance that a camel lift can lift the lifter past the base circle.
The gross valve lift refers to the cam lift multiplied by the rocker arm ratio. Subtracting the valve lash from the gross valve lift will give you the net valve lift.
- Duration: Duration is another common terminology used to refer to the total angle and camshaft degree that your valves are opened for.
The duration determines the power range of your engine. Typically, there are two types of durations: duration @ 50 and advertised duration.
Duration @ 50 refers to the duration measured in cranked degrees from the point a lifter rises to 50 thousandths of an inch from the base circle at the camshaft.
Advertised duration on the other hand refers to the total duration of the camshaft.
- Lobe separation: When a camshaft is manufactured, a lobe separation angle is grounded into it.
The lobe separation angle is the distance in degrees from the intake lobe to the exhaust lobe.
A slight discrepancy in the configuration of the lobe separation will cause the exhaust and intake valve to malfunction.
Comp Cams Catalog: Camshaft Details
Comp Cams master catalog includes a host of new engine parts, valve train, camshaft, lifter, and so much more all in one spot.
The importance of this catalog is that it makes finding details about a certain part of an engine fairly easy and straightforward.
With so many parts being developed year-in-year-out, it gets tougher every year keeping a tab on what is what.
Why gamble with details of your engine, when you can easily get the details about your engine from Comp Cams. The Comp Cams catalog can also help with making a proper camshaft selection.
To make the best possible selection involving a camshaft you need to know a lot about the application that is going into the type of car, transmission, gear ratio, rocker ratio, just to name a few.
After the information has been gathered, then you can pinpoint the application that will best suit your needs using this catalog.
So whether it be for drag race, marine, or street racing, you can easily determine, for example, the RPM to gun for.
No matter what your specific needs might be, whether it be an increase in torque, RPM, horsepower, or just the sound you’re looking for in a camshaft, trust Comp Cams.
How to Identify a Camshaft: Step by Step Guide
While a single-overhead-cam has one cam per bank, a dual-overhead-cam has two cams per bank. A single-overhead-cam transmits movement to the valves via the rocker arms, while a dual-overhead-cam has its camshaft directly over the valve stems.
The design of the camshaft is such that it is made up of cams arranged so that one set moves the intake valve, and the other set opens the exhaust.
In an engine equipped with two valves for exhaust and two valves for inlet, two camshafts are installed. In this case, one opens the exhaust gas while the other opens the inlet valves.
The camshaft is mainly identified by number. The camshaft identification number can be quite confusing to put together.
Nevertheless, when the number is broken down piece by piece, it becomes a lot easier to identify.
Step 1: Find the model prefix
One of the first things that come to mind when you are trying to identify a camshaft is the model prefix.
Mainly, the model prefix of a camshaft describes the type of vehicle the camshaft is compatible with. For example, if the camshaft has a model prefix of CE 3SGE, then the camshaft is ideal for a Toyota 3SGE.
Step 2: Find the grind or profile number
The next step to take when identifying a camshaft is finding the grind or profile number. The grind or profile number is often written on your camshaft followed by several degrees.
For instance, a camshaft can have an 899C stamp followed by a series of various numbers with degrees. The 899C stamp is your grind or profile number, take it and add it to your model prefix.
Step 3: Find the exhaust or exhaust grind number
Add the exhaust grind number to the end of the list of numbers. However, the model 0f your vehicle may or may not have an exhaust grind number.
In either case, if it is stamped onto the exhaust inlet of your car, it will follow the same format as the number on the camshaft.
Conclusion
In summary, now that you have a pretty good idea of what a camshaft does, you can apply that knowledge when next you are looking to purchase a used or new car.
If your reason for wanting to know what a camshaft does is to help you choose the best one, your focus should be on the cam camber, overlap angle, and maximum valve lift.
Do not compromise on the maintenance routine of a camshaft. The main cause of the failure of a camshaft is oil starvation.
For an engine to function, fuel-air mixture and spark are required with compression and a finite number of strokes to keep the engine working.