Editing How to make a timing tape

'''Making a semi-permanent timing tape is very easy, and removes any doubt as to where the timing marks are or were supposed to be- provided that:''' '''1.''' You know (or verify) that the "0" degree line on the damper or balancer (henceforth to be called a "damper") and the timing tab actually correctly represents "0" degrees (TDC). '''2.''' A method to find TDC is by using a piston stop and fabricate a timing "tab" (often a stiff piece of wire secured behind a convenient bolt) that aligns with the line on the damper to represent "0" or TDC. Help with this can be found at [[Determining Top Dead Center]]. Once TDC has been established, the rest goes like this: Using either a string, ruler or a seamstress' cloth tape measure, measure the circumference of the damper. If you only have a straight ruler, measure the diameter and multiply by 3.1416 (pi) to get the circumference. Once the circumference is known, 1/10 (10%) of this figure represents 36 degrees. Half of that is 18 degrees, half again is 9 degrees, etc. It doesn't matter what units are used to measure the circumference- metric, inch, or nanoparsec's. If you like precision, you can go this way, measure your damper's diameter, let's say it's 8 inches, first find the circumference, multiply 8 X 3.1416 = 25.1328, now to use a more accurate measuring system let's go metric, multiply your circumference of 25.1328 inches times 25.4 to convert to millimeters, which would be 638.37mm, now divide this by 360 and you'll get 1.77, this means that a mark on the tape of 1.77mm equals one degree, 17.7mm would be 10 degrees. When marking your home-made tape, starting from "0", BTDC will be to the right, ATDC to the left of "0". Careful measurement and marking of the degrees in this fashion on a length of masking tape can then be applied to the damper, aligning "0" on the tape to the line on the balancer, with the degrees BTDC to the right of this mark. If you are going to invest in a timing light, you might consider an inductive light with an "advance" feature. This allows you to read the timing from just the "0" point, the timing light will then adjust itself to show whatever amount of advance you want, or read the advance without regard for a timing tabs marks, except for an accurate "0" mark. They cost more than a standard light, but if you plan on tuning engines beyond the basics, it will pay for itself in the long run, IMHO. You can also measure the length between the timing tab marks and transfer them onto tape, i.e. if there's 3/4 of an inch (0.750") representing 10 degrees on the tab, two marks 3/4 of an inch (0.750") apart on your tape will also be ten degrees. This will work- provided that the timing tab is correct for the application and not for a different diameter damper. [[Category:Engine]] [[Category:Good articles]]

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