VTEC or Valve Timing Electronic Control is a system that's been used by Honda in passenger cars since 1991. I believe the 1991 NSX was the first production vehicle to get this system. It has since been used in several other Honda vehicles. Late model VTEC equipped vehicles use the iVTEC system which also changes cam timing as well as lift and duration. The system is designed to give you the 'best of both worlds'. You get to switch between 2 cam profiles. One for fuel economy, one for performance. A lot of people think that when VTEC kicks in you get an extra boost of power. Not true in my experience. It does however extend the torque curve to give you more performance after it does switch over. There is no set RPM where VTEC switches. The computer looks at several variables and calculates when to activate the VTEC solenoid. It's a cool system and for the most part rarely has issues. The most common issues I've seen with VTEC are the result of low, or incorrect oil viscosity. So if you have a VTEC engine, keep the oil topped off and make sure you use the viscosity listed on the oil cap. The animations are courtesy Honda Motor Company, thanks guys. The best place for answers to your automotive questions: http://www.ericthecarguy.com Facebook: https://www.facebook.com/EricTheCarGuy?fref=ts Twitter: https://twitter.com/EricTheCarGuy Google+: https://plus.google.com/100195180196698058780/posts Information on Premium Membership: https://www.ericthecarguy.com/premium-content-streaming-etcg-content Stay Dirty ETCG Due to factors beyond the control of EricTheCarGuy, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. EricTheCarGuy assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. EricTheCarGuy recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of EricTheCarGuy, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not EricTheCarGuy.