I think my outer harmonic balancer has moved a bit over the years on my 289, causing the timing mark to be off. I bought some timing tape and was wondering what the most accurate way of determining my exact tdc is.
If you think the balancer has moved, i'd just replace it.
TDC can be a pain to find with the engine in the car. You need a positive stop to screw into the spark plug hole. Rotate the engine by hand until it comes up against the stop and mark the balancer at the timing pointer. Rotate the engine the other way until it comes up against the stop and mark the balancer again. Then measure half way between the 2 scribe marks and that is TDC.
If you think the balancer has moved, i'd just replace it.
TDC can be a pain to find with the engine in the car. You need a positive stop to screw into the spark plug hole. Rotate the engine by hand until it comes up against the stop and mark the balancer at the timing pointer. Rotate the engine the other way until it comes up against the stop and mark the balancer again. Then measure half way between the 2 scribe marks and that is TDC.
As far as timing tape goes... I think i need to install some because I need to measure my total timing and the marks on my balancer don't go all the way to 40 degrees...
A few questions... what is the diameter of a 69 351w's stock harmonic balancer? If I jsut wanted to tune it, could I save a few bucks and use some masking tape + a sharpie to make some ghetto timing tape that extends to 45 or so degrees (just use the same spacing as the marks that are on there) and go by that?
It is a linear distance. Just measure and mark from 30. I did this yesterday, but I did not need the ghetto masking tape, I ust made marks on the balancer with a sharpie.