Timing Question

[A67StangMaster]

Ok this might seem stupid but i want to learn about it.
Dose anyone know how to time a cam, my dad has a timing light but he dose not want to teach me so dose anyone have any advice on how to use it and how to time a cam, what would you need too look for?

Thanks........

 

[D.Hearne]

There's no such thing as a dumb question. That said, you cannot time the cam with a timing light. There's really two different timing settings with an engine. One is the cam timing or rather the timing that affects the valve's opening and closing events. The other timing, which is what you use a timing light for, is ignition timing. This affects when the spark happens in relation to where the piston is on the compression stroke.

 

[grego37]

Is it ignition timing you're interested in learning about?

 

[A67StangMaster]

Well i need to know both because i am trying to rebuild an engine so later on i wont have to pay for expensive labor.

 

[streetstang67]

Cam timing should be pretty simple. Install the cam then when you put the timing chain on, line up the two 'dots'. As far as I know, thats the only way to mess with cam timing, and a sure way to get it right. As for the ignition, with the engine at #1 cyl. TDC, make sure the distributor rotor is pointing to the #1 plug electrode. That should get the car running. After that, you use the timing light to adjust the timing with the engine running by twisting the distributor.
Might not be detailed enough, but thats all I know.

 

[D.Hearne]

The simplest way to time the cam is to align the timing marks ( there's a "dot" on both the cam and crank gears) to where they're straight in line with each other, the crank dot at 12 o'clock, the cam gear dot at 6 o'clock. You can also "degree" the cam which is a more involved method to set the cam timing and more accurate, but takes a few more specialty tools and more time and experience to do. ---------Now to set the igniton timing, you need to get the #1 cylinder to Top Dead Center on it's firing stroke ( there's also a TDC on the exhaust stroke too, but you don't want it there to set the ignition timing) Then rotate the distributor to where the rotor is pointing closest to the #1 terminal on the dist cap. You can then ( if you have a points type distributor or a Pertronix unit and a few other brands of electronic systems-- don't try this with a Duraspark ) replace the rotor and cap, then slowly rotate the dist. body with the ignition on, and at least the #1 wire in place and something stuck into the plug terminal end to ground it near a ground source, rotate the dist body, and watch for the spark. When it does spark, stop the rotation and tighten the hold down bolt. When you check the timing with a light, it should be within 2 degrees of where you set it. With a light, you can set the timing by rotating the dist body with the engine running and pointing the light at the harmonic balancer. The light will flash and you'll be able to see the timing pointer line up with the marks on the balancer. When rotating the dist. body, the marks will move in relation to the pointer. NOW A WORD OF ADVICE----------- DO NOT TRY TO MOVE THE DISTRIBUTOR BODY ON A DURASPARK AND SOME OTHER MULTIPLE DISCHARGE UNITS WITHOUT WEARING THICK RUBBER GLOVES AND WEARING RUBBER SOLED SHOES. DOING SO WITHOUT PROTECTION WILL RESULT IN YOUR GETTING NAILED BY THE SPARK. EVEN WITH PROTECTION, YOU CAN GET HAMMERED , SO BE CAREFUL. AND TRY TO AVOID TOUCHING THE VEHICLE BODY WITH ANY OTHER PART OF YOUR BODY WHEN DOING SO THAT CAN ALSO RESULT IN YOUR GETTING HAMMERED BY THE SPARK.