engineContinuing in our quest to bring you the latest knowledge and education on GMC Trucks in Canada, we hone in, once again on variable valve timing under the hood of these impressive machines.  We already discussed a bit about the non variable types and how they operate with precision that is also limiting in terms of variation.  A variable valve timing situation allows for customization to fit the immediate needs of the engine in the Thunder Bay GMC trucks we discuss.

According to Jalopnik, a professional site on GMC trucks and other vehicles that invest in the latest feature to provide you the most in efficiency under the hood, the following is true, “Since modern gasoline engines incorporate the four-stroke cycle, this means that the camshafts rotate once for every two crankshaft rotations. To reinforce this point, consider the intake stroke of an engine. The intake valve is open, meaning the camshaft lobe is pushing against the cam follower and opening the valve.”

In these specific GMC trucks of Thunder Bay, along with other new cars and trucks that utilize the VVT feature, the intake valve is open, the piston moves down toward bottom dead center. Once the engine has reached bottom dead center, the crankshaft has rotated 180 degrees. Then the piston moves up to compress the fuel mixture. Once the piston has reached top dead center, the crankshaft has made a full rotation.  Directly following the above actions, your GMC trucks in Thunder Bay have engines that will allow spark plug ignites the fuel mixture, sending the piston back down to bottom dead center. It is after this that the crankshaft has turned one and a half full rotations and now the exhaust valve opens, and the piston moves back up to top dead center, marking a time where the crankshaft has rotated two complete times and the piston is almost top center once again.  The camshaft lobe that we are paying attention to is now back around, opening the intake valve, allowing the piston to move back down. What does all of this mean for you in your new GMC truck in Canada?  Well, on behalf of your Thunder Bay GMC truck Service Center we plan to explain more in the next post.