Variable Valve Timing Systems (VIDEO)

Variable Valve Timing Systems (VIDEO)

Variable valve timing systems allow today's engines to maximize performance and drivability.

CC:

There is nothing cooler than a camshaft because valve lift, duration and timing have drastic effects on engine performance.

Before the development of variable valve timing and variable valve lift systems, these were all fixed specifications, and performance compromises had to be made depending on the use of the vehicle.

Today, a modern engine that utilizes a form of VVT is able maximize performance and driveability throughout its entire operating range.

There are two different types. Early VVT systems were considered discrete, and they worked using a stepped adjustment, with one timing setting for a lower RPM range, one for a higher RPM range.

The advancement of these systems brought us continuously variable valve timing, and through cam phasing, the PCM is able to make continuous adjustments for peak performance in all conditions and all operating ranges.

Cam phasing refers to rotation of the camshaft via an actuator, to advance or retard the camshafts on a VVT system.

Systems that vary valve lift and duration are much more complex, with the use of multi-profile camshafts and rocker arms, as well as a multitude of other designs.

The crankshaft and camshaft sensors are the primary inputs for system operation because they monitor the relationship between the crankshaft and camshaft positions, but there may also be many other sensors and solenoids that affect operation, depending on the system.

What this means is that diagnosing these systems requires the use of a full function bi-directional scan tool to view engine data and operating parameters, as well as perform functional testing of the system.

Thanks for watching The Striking Point from TechShop. I’ll see ya next time.

You May Also Like

How-to Complete Emissions Monitors Faster

This video will focus on how a product like CAT COMPLETE can improve the chances of completing the monitors faster. This video is sponsored by Rislone.

For some emissions-related repairs like oxygen sensors and catalytic converters, a lot of time can be spent confirming the repair by trying to complete the vehicle emissions monitors. To complete or force a monitor requires driving the vehicle under specific conditions. The emissions drive cycle might include getting the vehicle to closed loop operation and performing four or five periods of accelerating from 30 to 45 miles an hour. Other manufacturers might require driving at freeway speeds. 

How Important is Regenerative Braking For EVs?

Regenerative braking helps to increase the overall efficiency and range of the EV, increasing the range of an EV by up to 20%.

Get to Know Performance Ride Technology

PRT is a global OE supplier with more than 5,000 products available in the United States.

PRT Heavy Duty Highlights Shocks for CV Applications

Learn to install PRT Heavy Duty’s gas-charged shocks for enhanced driving stability in trucks and buses.

Why You Should Replace The Thermostat

It is always best practice to replace the thermostat on a vehicle after it has overheated. Sponsored by Auto Value and Bumper to Bumper.

Other Posts

Tensioner Tech Assist

The Lift and Pin is designed to simplify tensioner replacement and belt installation.

EV Cooling Systems

The large batteries that EVs carry need to be maintained within a specific temperature range for optimal performance.

What Constitutes A Complete Brake Job?

Complete, safe brake jobs are key. This video is part of the Group Training Academy.

Decoding Brake Pull Issues

Addressing brake pulls requires diagnostic dedication. This video is part of The Group Training Academy.