How To Cam A Vtec ⋆ binaryage.com

Understanding VTEC Technology

VTEC (Variable Valve Timing and Lift Electronic Control) is a groundbreaking valve train technology developed by Honda that revolutionized engine performance and efficiency. It enables optimal valve timing and lift adjustments to enhance power output, fuel economy, and emissions control.

VTEC operates by utilizing a unique rocker arm system. At lower engine speeds, one intake and one exhaust valve are opened by two separate cam lobes. As the engine revs higher, a solenoid triggers the engagement of a locking pin, which combines the two rocker arms. This allows a single cam lobe to control both valves, resulting in higher valve lift and longer duration.

The switch between low- and high-cam profiles occurs at a predetermined engine speed, typically around 5,000 rpm. This transition creates a “VTEC engagement point,” where a noticeable surge in power and responsiveness can be felt. By optimizing valve timing and lift across different engine speeds, VTEC maximizes airflow, reduces pumping losses, and increases overall engine efficiency.

The following table summarizes the key benefits of VTEC technology:

Benefit	Explanation
Increased power	Optimizes valve timing and lift for maximum airflow and combustion efficiency.
Improved fuel economy	Reduces pumping losses and optimizes airflow for better fuel efficiency, especially at lower engine speeds.
Reduced emissions	More efficient combustion process reduces emissions of harmful pollutants such as hydrocarbons (HC), nitrogen oxides (NOx), and carbon monoxide (CO).

Preparation: Tools and Materials

Gathering Essential Tools

To ensure a successful camming project, it is crucial to gather all the necessary tools. Here’s a detailed list of items you’ll need:

Valve spring compressor: Specialized tool for safely compressing valve springs.
Timing belt tools: A set of specific tools to set and adjust valve timing.
Torque wrench: Essential for applying precise torque to bolts and nuts.
Socket wrenches: A complete set of socket wrenches in various sizes.
Wrenches: Both open-end and combination wrenches are required for reaching tight spaces.
Feeler gauge: Used to measure valve clearances.
Lubricants: Cam assembly and timing belt lubricants to ensure proper lubrication.
Measuring tools: Micrometer or digital calipers for precise measurements.
Safety glasses: Always protect your eyes while working.
Gloves: To prevent cuts and abrasions.

Materials List

In addition to tools, you’ll also need the following materials:

Material	Purpose
Camshaft	The new camshaft you will be installing
Intake valve guide seals	To seal the intake valve stems
Exhaust valve guide seals	To seal the exhaust valve stems
Valve stem seals	To seal the valve stems
Valve spring retainers	To hold the valve springs in place
Valve keepers	To secure the valve springs
Timing belt	To connect the camshaft to the crankshaft

Locating the VTEC Solenoid

The VTEC solenoid is usually mounted on the cylinder head or intake manifold. In some cases, it may be located on the side of the engine block. To locate it, follow these steps:

Identify the intake manifold. It is typically a large, black plastic or metal component that sits on top of the engine.
Look for a small, cylindrical solenoid with two wires connected to it. This is the VTEC solenoid.
If you cannot find the VTEC solenoid on the intake manifold, check the side of the engine block.

Additional Tips

Here are some additional tips for locating the VTEC solenoid:

Consult your vehicle’s service manual for specific instructions on how to locate the VTEC solenoid.
If you are having trouble locating the VTEC solenoid, ask a qualified mechanic for assistance.

Location	Description
Intake manifold	Mounted on the intake manifold, usually near the throttle body
Engine block	Mounted on the side of the engine block, usually near the oil filter

Removing the VTEC Solenoid

Before working on the vehicle, ensure it’s parked on a level surface, and the engine is cold. Locate the VTEC solenoid, which is typically situated on the front or side of the engine. It might have two or three wire connections. Unplug the electrical connector first by pressing the release tab and gently pulling the connector away from the solenoid.

Disconnecting the Oil Lines

Disconnect the oil lines connected to the VTEC solenoid. Depending on the vehicle, you may encounter one or two oil lines. Use a wrench to loosen the banjo bolts securing the oil lines. Carefully remove the bolts and the washers beneath them to detach the oil lines. Cover the open ports on the solenoid and the engine with clean rags to prevent oil leakage.

Removing the Mounting Bolts

Locate the mounting bolts that secure the VTEC solenoid to the engine. typically, there will be one or two bolts. Use a wrench or socket to loosen and remove the bolts. Once the bolts are removed, carefully lift the VTEC solenoid straight up and off the engine. Handle it with care to avoid damaging any internal components.

Tools Needed
Adjustable wrench or socket set
Rags
Flashlight (optional)

Installing the Cam

Installing the cam is a critical step in the camming process. Here’s a detailed guide to ensure a successful installation:

1. Set Top Dead Center (TDC)

Locate the timing marks on the camshaft and crankshaft and align them to TDC. This ensures that the pistons are at the top of their compression stroke.

2. Remove the Cam Sprocket

Using a specialized camshaft holder, remove the cam sprocket by loosening the bolt. Remove the sprocket and its key.

3. Remove the Cam Cap Bolts

Locate and remove all the cam cap bolts. Use a torque wrench to prevent overtightening or loosening.

4. Pry off the Cam Caps

Gently pry off the cam caps using a flathead screwdriver. Be careful not to damage the cam or cylinder head.

5. Remove and Install the Cam

Carefully remove the old camshaft from the cylinder head. Ensure that the cam lobes are facing upwards. Lubricate the new camshaft and install it into the cylinder head. Make sure the orientation marks on the cam and sprocket align correctly.

Step	Description
5a	Check for clearance between the camshaft and the cylinder head. Use feeler gauges or plastigage to measure the gap.
5b	Adjust the camshaft position if necessary. Loosen the cam sprocket bolt and rotate the cam until the desired clearance is achieved.
5c	Tighten the cam sprocket bolt to the specified torque. Reinstall the cam caps and bolts, following a star pattern to ensure even tightening.

6. Install the Sprocket and Timing Chain

Install the cam sprocket and its key. Install the timing chain onto the cam sprocket and crankshaft, ensuring the timing marks align correctly.

Adjusting Cam Timing

Adjusting cam timing is a critical step in the process of camming a VTEC engine. It involves aligning the camshafts with the crankshaft so that the valves open and close at the correct times. This ensures that the engine runs smoothly and efficiently.

Step 1: Remove the Timing Belt

To adjust cam timing, the first step is to remove the timing belt. This involves loosening the tensioner and removing the belt from the sprockets.

Step 2: Align the Cam Gears

Once the timing belt is removed, the cam gears can be aligned. This is done by matching the marks on the gears with the corresponding marks on the engine.

Step 3: Install the Timing Belt

Once the cam gears are aligned, the timing belt can be installed. It is important to ensure that the belt is tensioned correctly.

Step 4: Adjust the Tensioner

After the timing belt is installed, the tensioner must be adjusted. This is done by turning the tensioner until the belt is properly tensioned.

Step 5: Verify Cam Timing

Once the tensioner is adjusted, it is important to verify the cam timing. This can be done by using a timing light or a dial indicator.

Step 6: Fine-Tune Cam Timing

If the cam timing is not correct, it can be fine-tuned by adjusting the cam gears. This is a delicate process that requires experience and patience. The following table provides some tips for fine-tuning cam timing:

Adjustment	Effect
Advance cam timing	Increases power at low RPM
Retard cam timing	Increases power at high RPM
Increase overlap	Improves intake and exhaust flow
Decrease overlap	Reduces intake and exhaust flow

It is important to note that fine-tuning cam timing is not necessary for all VTEC engines. However, it can be beneficial for engines that are used for racing or performance applications.

Reinstalling the VTEC Solenoid

The VTEC solenoid can be replaced by reversing the removal steps. It’s important to ensure that the new solenoid is properly seated and tightened to prevent any leaks. Here are the detailed steps for reinstalling the VTEC solenoid:

Clean the mating surfaces of the solenoid and the VTEC spool valve body.
Apply a small amount of high-temperature sealant to the O-rings on the solenoid.
Carefully align the solenoid with the spool valve body and insert it into place.
Tighten the solenoid mounting bolts to the specified torque using a torque wrench.
Reconnect the electrical connector to the solenoid.
Check for any leaks by starting the engine and allowing it to run at idle for a few minutes.
Inspect the solenoid area for oil leaks. A common location for leaks is the connection between the solenoid and the spool valve body.
If any leaks are discovered, remove the solenoid, clean the mating surfaces thoroughly, and reassemble the components with fresh O-rings and sealant.
Once the solenoid is properly installed and leak-free, reset the ECU by disconnecting the negative terminal of the battery for a few minutes.
Reconnect the battery and start the engine to allow the ECU to relearn the VTEC system parameters.

Torque Specifications	Bolt Size	Tightening Torque
Solenoid Mounting Bolts	M8	10 Nm (7.4 ft-lbs)

Wiring the Cam

To wire the cam, you will need the following:

A camshaft
A camshaft pulley
A camshaft timing belt
A camshaft position sensor
A camshaft position sensor harness
A camshaft position sensor connector
A wire crimper
A pair of wire strippers

Once you have gathered all of the necessary materials, you can begin the process of wiring the cam.

Install the camshaft pulley. The camshaft pulley is responsible for driving the camshaft timing belt. To install the camshaft pulley, simply slide it onto the camshaft and tighten the bolt that holds it in place.
Install the camshaft timing belt. The camshaft timing belt is responsible for synchronizing the camshaft with the crankshaft. To install the camshaft timing belt, simply loop it around the camshaft pulley and the crankshaft pulley. Make sure that the timing marks on the belt are aligned with the timing marks on the pulleys.
Install the camshaft position sensor. The camshaft position sensor is responsible for sending a signal to the engine’s computer when the camshaft is at a certain position. To install the camshaft position sensor, simply bolt it to the engine block. Make sure that the sensor is aligned with the timing mark on the camshaft.
Install the camshaft position sensor harness. The camshaft position sensor harness is responsible for connecting the camshaft position sensor to the engine’s computer. To install the camshaft position sensor harness, simply plug it into the camshaft position sensor and the engine’s computer.
Install the camshaft position sensor connector. The camshaft position sensor connector is responsible for connecting the camshaft position sensor harness to the engine’s wiring harness. To install the camshaft position sensor connector, simply plug it into the camshaft position sensor harness and the engine’s wiring harness.
Test the camshaft position sensor. Once the camshaft position sensor is installed, you can test it by using an ohmmeter. To do this, simply connect the ohmmeter to the camshaft position sensor terminals. The ohmmeter should read a resistance of between 500 and 1000 ohms.
Adjust the camshaft timing. Once the camshaft position sensor is tested, you can adjust the camshaft timing. To do this, simply loosen the camshaft pulley bolt and rotate the camshaft until the timing marks on the belt are aligned with the timing marks on the pulleys.
Tighten the camshaft pulley bolt. Once the camshaft timing is adjusted, tighten the camshaft pulley bolt. Make sure that the bolt is tightened to the specifications in the engine’s service manual.

Cam Wiring Task	Difficulty	Time Required
Installing the camshaft pulley	Easy	15 minutes
Installing the camshaft timing belt	Moderate	30 minutes
Installing the camshaft position sensor	Easy	15 minutes
Installing the camshaft position sensor harness	Easy	15 minutes
Installing the camshaft position sensor connector	Easy	5 minutes
Testing the camshaft position sensor	Easy	5 minutes
Adjusting the camshaft timing	Moderate	30 minutes
Tightening the camshaft pulley bolt	Easy	5 minutes

Troubleshooting Tips

1. Wrongly timed camshafts

Incorrectly timed camshafts are one of the most common causes of engine issues. If the camshafts are not timed properly, the valves will not open and close at the correct time, which can cause a loss of power, rough idling, and other problems.

2. Worn or damaged camshafts

As camshafts age, they can become worn or damaged, which can lead to a variety of problems. Worn camshafts can cause a loss of power, reduced fuel efficiency, and other issues.

3. Faulty camshaft sensors

The camshaft sensors are responsible for sending signals to the engine’s computer, which uses these signals to control the timing of the camshafts. If the camshaft sensors are faulty, the computer may not be able to control the timing of the camshafts properly, which can lead to a variety of problems.

4. Faulty variable valve timing (VVT) system

The VVT system is responsible for adjusting the timing of the camshafts in order to improve engine performance. If the VVT system is faulty, the camshafts may not be able to adjust their timing properly, which can lead to a loss of power, reduced fuel efficiency, and other issues.

5. Faulty valve springs

The valve springs are responsible for keeping the valves closed when they are not supposed to be open. If the valve springs are faulty, the valves may not be able to close properly, which can lead to a loss of power, reduced fuel efficiency, and other issues.

6. Faulty valve lifters

The valve lifters are responsible for opening and closing the valves. If the valve lifters are faulty, the valves may not be able to open or close properly, which can lead to a loss of power, reduced fuel efficiency, and other issues.

7. Faulty timing chain or belt

The timing chain or belt is responsible for connecting the camshafts to the crankshaft. If the timing chain or belt is faulty, the camshafts may not be able to rotate properly, which can lead to a loss of power, reduced fuel efficiency, and other issues.

8. Faulty oil pump

The oil pump is responsible for circulating oil throughout the engine. If the oil pump is faulty, the camshafts may not be able to get enough oil, which can lead to premature wear and damage.

9. Camshaft actuators or solenoids

Camshaft actuators or solenoids are responsible for controlling the flow of oil to the VVT system. If the camshaft actuators or solenoids are faulty, the VVT system may not be able to adjust the timing of the camshafts properly, which can lead to a loss of power, reduced fuel efficiency, and other issues.

Problem	Possible Cause
Loss of power	Wrongly timed camshafts
Rough idling	Worn or damaged camshafts
Reduced fuel efficiency	Faulty camshaft sensors
Engine knocking	Faulty VVT system
Valve noise	Faulty valve springs
Engine overheating	Faulty valve lifters
Engine seizing	Faulty timing chain or belt
Premature camshaft wear	Faulty oil pump
Incorrect camshaft timing	Faulty camshaft actuators or solenoids

Safety Precautions

Before starting any work on your engine, it is crucial to take appropriate safety precautions. Ensure your vehicle is parked on a level and stable surface, engage the parking brake, and disconnect the battery’s negative terminal. Wear appropriate safety gear, including gloves, safety glasses, and earplugs, to protect yourself from potential hazards.

Maintenance

Maintaining your V-TEC engine is essential for optimal performance and longevity. Regular oil changes are vital; use high-quality oil and follow the manufacturer’s recommended change intervals. Replace spark plugs according to the recommended schedule. Inspect and clean the air filter to ensure adequate airflow. Keep the cooling system in good condition by flushing coolant periodically and ensuring proper thermostat operation.

Checking Valve Clearance

Checking valve clearance is a critical part of V-TEC maintenance. Over time, valves can become worn, leading to decreased performance and potentially serious engine damage. To check valve clearance, you will need a set of feeler gauges and a spark plug wrench. Carefully remove the spark plugs and measure the gap between the camshaft and valve stem using the feeler gauges. Adjust the valve clearance as necessary according to the manufacturer’s specifications.

Timing Belt Replacement

The timing belt is a vital component that synchronizes the movement of the camshaft and crankshaft. Failure of the timing belt can result in catastrophic engine damage. Refer to the manufacturer’s maintenance schedule for the recommended replacement interval and follow the specified procedure for replacing the timing belt.

Valve Cover Gasket Replacement

The valve cover gasket seals the connection between the valve cover and the cylinder head. A worn or damaged gasket can cause oil leaks. To replace the valve cover gasket, remove the valve cover and clean the mating surfaces. Apply a new gasket to the valve cover and reinstall it, following the manufacturer’s instructions.

Spark Plug Removal

Spark plugs should be removed and inspected periodically. To remove spark plugs, disconnect the ignition coils and use a spark plug wrench to loosen and remove them. Check the condition of the electrodes and gap the plugs as necessary before reinstalling them.

How to Cam a VTEC

VTEC (Variable Valve Timing and Lift Electronic Control) is a variable valve timing system developed by Honda. It allows the engine to switch between two or more cam profiles, depending on engine speed and load. This can improve engine performance, fuel economy, and emissions.

To cam a VTEC engine, you will need the following tools and materials:

VTEC camshaft

VTEC oil control solenoid

VTEC pressure sensor

VTEC computer

Wiring harness

Tools required to remove and install the camshaft, oil control solenoid, pressure sensor, and computer.

Once you have these tools and materials, you can begin the process of camming a VTEC engine.

Steps:

Remove the old camshaft.
Install the new VTEC camshaft.
Install the VTEC oil control solenoid.
Install the VTEC pressure sensor.
Install the VTEC computer.
Install the wiring harness.

Once you have completed these steps, your engine will be cammed to VTEC. You will need to have the engine tuned by a qualified technician to ensure that it is running properly.