Q: What does ‘dialling in a cam’ mean and how do I go about it?

A: Dialling in a cam simply means, making sure the camshaft is set up in the Engine as close as possible to the Camshaft Specification sheet supplied by the Cam grinding specialist In most cases our Camshaft Data Sheet will have a Lift at TDC (Top Dead Centre) figure as well as the opening and closing events.

We find using the lift at Top Dead Centre method to be the simplest and most effective. First you must establish Top Dead Centre (TDC) accurately.

Once TDC is achieved, with the camshaft in place, insert a Cam Follower into the No. 1 Intake Lifter bore.

Now place a pushrod onto that cam follower and mount a Dial Indicator so it is in line with the pushrod.

Make sure the cam follower is on the heal (bottom) of the lobe and Zero the dial indicator.

For chain driven camshafts, rotate the camshaft in the same direction of Crankshaft rotation until the lift at TDC stated on your Camshaft Data Sheet is achieved.

Now you can install the chain and sprocket set.

For gear driven camshafts such as Holden 6cyl: the camshaft will rotate in the opposite direction to the crankshaft.

Q: How do I check for Top Dead Centre?

A: The best way to check for Top Dead Centre, is by using what is called the ‘positive stop’ method.

First you must mount a Degree Wheel onto the front of the crankshaft and rotate the engine until No.1 piston is approximately at the TDC position.

Set up a piece of wire as a pointer and position it on Zero or TDC.

Turn the crankshaft in the opposite direction of normal rotation until the piston has gone down the cylinder bore about 20 Degrees of rotation.

Now screw the piston stop into the spark plug hole until the stop just touches the piston.

Mark the degree wheel and continue to rotate the crankshaft in the same Direction until the piston comes back up the cylinder bore and the piston again touches the stop.

Mark the degree wheel once again. Half way between the two marks will be true TDC.

Q: Which type of cam should I use, Hydraulic or Solid?

A: It really comes down to what you are using the engine for.
Is it a competition engine or one which will be used mainly for every day use?
In most cases, if the engine isn't going to be used above 5500 RPM then a hydraulic profile should be adequate.

If however, the engine is going to be used around the 6000 - 6500 rpm range, then you can still use what is known as Anti Pump Up Hydraulic lifters.
Revving the engine higher than 6500 rpm would require using solid lifters.
 

Q: Can I use my old Cam Followers / Rockers

A: The short answer to this question is NO.
When installing a new camshaft, the cam followers/ Rockers should be replaced either with new ones or refaced  followers/rockers. At Wades we provide a full refacing service. In most cases this is more economical making savings of up to 50%.
Most cam followers known as flat followers, are not actually flat at all but have a spherical radius on their contact face. This radius helps the lifter to rotate on the cam lobe to reduce lifter wear.
 

Q: Should I use stronger valve springs?

A: A lot of people think, because they have replaced their old camshaft with a modified one, that they should use Stronger Valve Springs. This is not necessarily the case at all. It depends on the application and design of the camshaft itself.

It is better to use the lightest spring possible for the camshaft being used, the heavier the spring is, the more chances of premature camshaft wear.

Q: Do I have to “Run In” the camshaft?

A:Yes
The most important thing is to make sure the engine has good oil pressure as soon as it fires up.

Do not keep cranking the engine over and over as this will only wipe off any oil that was on the camshaft and will cause the cam to scuff.

If the engine does not start straight away, find the problem and start over making sure the cam and lifters have adequate lubrication.

There are many different theories on running in a camshaft. A lot of engine builders run the engine in with light valve springs for the first 30 minutes or so but that is not always possible or convenient.

We suggest you run the engine for approx 15-20 minutes at light throttle but don't let it overheat. That way the engine should maintain good oil pressure and lubrication for all the components.