Compression Stroke & Top Dead Center

Locate the compression stroke and TDC easily! I show you how to find the compression stroke with the valve covers on and with the valve covers off. I explain how to find TDC using preexisting marks on the harmonic balancer and how to find TDC if there are no marks on the balancer.

*If you have no marks on the balancer, you will need timing tape and a piston stop that fits your heads.

How to find diameter of the harmonic balancer using circumference: Sometimes it's hard to get an accurate diameter measurement and easier to measure the circumference. If you're able to measure diameter easily, great! If not, circumference is the way to go. You'll need some fabric measuring tape and some basic math skills! Here's an example:

Circumference of balancer is: 21"
We need to find Diameter in order to figure out what timing tape to use.

Circumference = 2 x 3.14(pie) x radius, so let's plug in our number

21 = 2 x 3.14 x radius
21/3.14 = 2 x radius -Divide 21 by 3.14
6.7 = 2 x radius -Our result from the equation above
6.7 / 2 = radius -Divide 6.7 by 2 to get the radius
3.35 = radius -Our result from the equation above

Diameter = 2r, so our radius is 3.35 x 2

D= 6.67 - Our answer from the equation above

As you probably noticed, you can stop once you divide circumference by pie, but I wanted to be thorough and show the entire equation.