These two phrases are sometimes used to mean the same thing. In reality, they are two separate processes, but both are important to produce a properly performing camshaft.

Cam profile design is my main focus. This is the actual designing process of the cam lobe. Most of the information in this blog section describes what is involved in designing a cam profile. Hopefully, you have read all of the posts so far, and have a good understanding about cam profile designs.

Camshaft design is different from cam profile design. Once the cam profiles are designed, the next step is to make the camshaft. Obviously, making the camshaft is much more involved. There are many stages in the camshaft manufacturing process. From the material to make the camshaft, heat-treating, indexing the lobes, gear cutting, machining and grinding equipment used, quality control, all the way through to the packaging to ship the finished camshaft. I’m sure you will be glad to hear, that I have no desire to describe in detail, the manufacturing process. It is easy enough to imagine all that is involved.

The part of camshaft design that most of you are interested in is, what camshaft do I need for my application? That will involve the choosing of the correct camshaft core, the proper profiles, lobe separation angle, and the camshaft indexing in relation to the crankshaft. All of these choices have to be correct, or the camshaft will not perform as well as it could. No doubt, a big task for the person picking the camshaft. If you find someone that can routinely choose the correct camshaft for the application, stick with that person. There are also software programs written to do this. From my experience, the programs that really work are expensive. They are marketed more towards a company than an individual.

As you can see, cam profile design and the camshaft design, must work together. You can have the best cam profiles, but if the camshaft design is poor, the camshaft does not perform well. The cam profile designs are blamed along with the camshaft and the manufacturer. You can also have cam profiles that are not correct for the application, but the camshaft design is good. The camshaft will generally perform ok, but not as well as it would with the proper cam profiles. This is the most common problem with camshafts today.

If you are new to my blog page, please start at the beginning and read all of my posts. You will have a better understanding of cam profiles and my approach to cam profile designs.

If the cam profile lift table is the same on the opening and closing side, the profile is symmetrical. If the lift table is not the same, the profile is asymmetrical. Simple enough…right? You must study and graph the lift table of any cam profile to truly understand the profile. The lift table is the blueprint of a cam profile.

Most of the early modern cam profile designs were symmetrical. When I speak of modern cam profiles, I mean a computer was used in the design process. Symmetrical profiles were easier to design and the knowledge available, at the time, was just in the beginning stages. Asymmetrical profiles were created when the opening and closing ramps became different. This is because the valve can be opened faster than it can be closed. Most cam profiles today are asymmetrical.

In most conventional cam profiles, the opening and closing ramps are what make the profile asymmetrical. This causes some of the main profile to also be asymmetrical. Usually from the end of the ramp to around .050 tappet lift, the profile will be asymmetrical. As you move up the lift table to maximum lift, the profile will become less asymmetrical. On either side of maximum lift, the profile will actually be symmetrical for many degrees. The major asymmetry is in the low lift areas of the profile. The higher lift areas may be asymmetrical, but not by very much. Again, the only reason the profile is asymmetrical, is that the opening and closing ramps are designed differently. There is no magic going on here to try and manipulate the air flow.

For an unconventional cam profile, the entire opening and closing side of the profile is intentionally designed different. This is because the rocker ratio is not consistent (as in a conventional profile) throughout the valve movement. Usually, you can see the different shape of the opening and closing side of the lobe. This type of profile is highly asymmetrical and must be designed that way for a smooth valve motion.

Conventional symmetrical cam profiles are still designed today. There is nothing wrong with them. Just because a cam profile is symmetrical, doesn’t mean that it is a poor design or inferior.

If you haven’t noticed, the website has a new domain name (web address).
www.camprofiledesigns.com

This is a registered address that belongs to me. Having a registered address is more professional and it makes the website easier to find in search engines. It is just another ongoing development in the website. I created this website and constantly update and develop it myself. I am certainly not a professional website builder, but if you are someone wanting to build your own website, I would be glad to offer any help to you.

Be sure to update your bookmark to this new address. The system will automatically forward you from the old address until you change.

Check back, I will have a new technical post soon.