There are some terms in the extensive fields of automotive industry that can be a bit elusive or just plain loose with definition. One aspect of this comes with camshafts–the part of the rotating assembly allowing our engines to breathe in gas and air and breathe out burnt exhaust fumes. For example, people talk about how mild or aggressive a cam can be, but what factors determine this kind of description?

Lunati makes it easy for us to understand the ins and outs of camshafts with a handy guide now available on their website. In it, you’ll find all sorts of terms that may have befuddled you for years, clearly explained and illustrated, along with what differentiates this cam from that one.

In every cam, the basics remain the same: to provide a way for the air-fuel mixture to quickly and cleanly be entered into and shoved out of the combustion chamber amidst a four-stroke cycle. Ramps on either side of a lobe can be made longer or shorter to increase or decrease the lifter’s duration during a cycle. They include the opening, closing, and lash ramps.

Where camshafts differentiate are in symmetrical or asymmetrical design. Most early motors were known for using symmetrical designs, more for ease of production than anything else. On either side of the lobe center line, the ramps were made to be mirror opposites so that there was little overlap in valve lift duration.

Nowadays, the symmetrical design is all but gone thanks to the asymmetrical camshaft. Most asymmetrical cams lift quickly and seat both valves slowly, and have become the preferred choice when crafting engines.

If you ever find yourself scratching your head over cams and their terms, hop onto the Lunati website and peruse their Tech section for this and other great guides to automotive components. And if you’re a Facebook user, Lunati’s page is the place you want to go for updates on promotions, photos, event news, and more.