Originally Posted by
Connedrod
The reason to and how to find tdc is quite obvious. He is so up some poor sod for being out one degree in the mag time ffs. And no it isn’t easy btw to actually find true tdc.
Well, actually, it was 3 degrees, 25 degrees BTDC vs 22 degrees BTDC. Yeah, that's well outside of tolerance. There's errors inherent in every method of determining TDC, including with a dial indicator, but I'm pretty sure that the method with the "locator" screwed into the spark plug hole and the protractor on the spinner is accurate enough to detect a 3 degree error. It is, after all, the method that Teledyne Continental specifies in their MSB about magneto timing.