2, 10, & 11o'clock timing, relative or absolute?

[jts359]

I want see where this post goes as I am having the same problem with my 347 , I set the engine on TDC and put a mark on the harmonic balancer , I then start the engine and and with a timing light I can not find that mark , Its about 90 degrees away from where I would expect to find it , I set the engine up with a vacuum gauge and it runs great , Someday I'll find that mark , Ed