Engineering Explained on MSN

Variable valve lift vs variable valve timing - VVL vs VVT

What is VVL? What is VVT? How does VVL/VVT work? 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 ...
Hot Rod

Variable Valve Timing - The Next Phase

Once upon a time, picking a cam for a given engine combo was all about compromise: improve top-end power at the expense of low-end torque, run well at wide-open throttle but sacrifice idle stability ...