In order to set a stage for what follows, let's first revisit some of the fundamentals involved in how valve timing relates to power output. And to further clarify how "power" is defined in the ...

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 ...

Without variable valve timing, these intake and exhaust valves would operate in the same manner regardless of the engine’s RPM (revolutions per minute) speed or the driving environment. This isn’t ...

The language of import performance can be strange. Sometimes it's a verbal stew of numbers and letters--RX-8, NSX, and MR2, for example--that seem randomly tossed together. At other times it adopts ...

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 ...

Every aspect of an engine is a compromise: torque for horsepower, efficiency for emissions, performance for fuel economy, compression for octane tolerance. During the evolution of the internal ...

Despite current efforts to revisit light-vehicle fuel economy standards enacted during the Obama administration, there have been no changes to the law, and there might not be for years, as the wheels ...

Getting air in and exhaust gases out of the combustion chamber under all speeds and driving conditions is essential for a car’s fuel efficiency and low emissions. That’s why virtually all Chevrolet ...

What is variable valve lift? What is variable valve timing? We're going to look at the valvtrain from a 2009 Audi 2.0L I4 Turbo engine to check out the differences. Variable valve lift is used to ...

Variable valve timing isn’t necessarily a new idea, but it is new to BMW motorcycles. With a freshly designed 1,254 cc two-cylinder flat engine, VVT is arriving in BMW bikes for the first time with an ...