Cars are intricate machines that rely on a series of chemical and mechanical processes to work properly. When things go wrong with one of those processes, your car can start to make some strange ...

A few days ago, we published a report highlighting the valve lifter issues some General Motors customers were experiencing in certain vehicles equipped with either its 5.3L V8 L84 gasoline engine or 6 ...

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 ...

General Motors has issued a service update for 2021 model year full-size truck and SUV models that are being shipped to dealerships and may be affected by valve lifter problems. The hazards: this ...

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 ...

The engines of yesteryear were pretty simple, with tappets clackity-clacking away on cam lobes, opening valves, and making a ruckus while doing it. Mechanical lifters were adequate for valve operation ...

Before the implementation of hydraulic lifters to keep the engine's valves in proper working order, regular adjustment was required to maintain the critically necessary clearance in the valvetrain.

The typical four-stroke engine is made up of hundreds of parts. These parts are all designed and engineered to work together to make a prescribed amount of power, torque, engine longevity, and other ...

Give them the results of a TDC valve-drop static clearance test, and Comp Cam's techs can calculate the piston-to-valve clearance for any of its cams at any degree of rotation. This is especially ...