I know my timing is not right. Getting on it in 2nd gear, it starts cutting out in mid-range. I have a '67 bird with a 68 400, 375 cam, 4X heads, Edelbrock Performer and AFB knockoff, and 77 HEI. 4-speed M-20. Any tips for initial timing, total timing, mechanical and vacuum advance? Haven't found a timing tape for the harmonic balancer. It's a warm weather (Houston) car.