The tough guy in you says to stab that cam in retarded a few degrees for maximum top-end horsepower, while your more practical alter ego suggests advancing it a hair for improved low-end torque and ...

Variable valve timing (VVT) and variable valve lift (VVL) have very similar names, both referring to variable valve performance. Does that mean that they are basically the same thing? The are most ...

The jargon goes well beyond just names. Car specs are full of abbreviations that may or may not have any meaning at first glance. And sometimes we get so used to seeing those abbreviations that we may ...

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 ...

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 Mitchell mechanical Variable Valve Timing (VVT) system is described. The way in which it exploits variable angular velocity to change valve timing is explained. The system was used in a programme ...

COVID-19 has been unkind to even the healthiest of businesses, but to already-troubled companies like the storied Harley-Davidson, the pandemic came as an unwelcome wildcard. With its dated lineup and ...

To celebrate HOT ROD's 75th anniversary, we teamed up with CASTROL GTX to bring you some of the stories that exemplify the core of what HOT ROD is and reflect the brand's influence on America's car ...

When Chevrolet announced that the fifth-generation Camaro would come with two different V-8 engine depending on what transmission the customer ordered, many enthusiasts were a bit confused. The LS3, ...

Harley-Davidson has filed a patent application for a variable valve timing (VVT) V-twin engine, possibly for the Sportster to improve economy and reduce emissions. The iconic American manufacturer has ...