Manufacturers like to use a lot of acronyms on their cars. Variable valve lift (VVL) and variable valve timing (VVT) are two of the most popular ones. These systems sound pretty similar, but what do ...

Engines are complex bits of machinery. At their core level, yes, it's easy to understand what is happening. Air and fuel enter the engine where they are ignited and combustion occurs resulting in ...

Valve overlap—that crucial interval when both the intake and exhaust valves are open, expressed in degrees of crankshaft rotation—is typically a fixed parameter and always a compromise. For example, ...