360 timing, help

ok here are the number: Mecanical advance set at 14, vaccum advance 21.
Idle 900 rpm, initial advance 18, 12 in of vaccum, total advance 53 at 1800 rpm.

The timing was all wrong before, was using the wrong mark on the damper. PLS, DON'T LAUGH AT ME. Run good now but ping a little bit at part throttle and tend to diesel when shut off.
Had the best vaccum at initial advance of 20, getting 14" of vaccum. But was pinging more. Total advance seems to be too early, should i use bigger spring or reduce mecanical advance.

P.S. new gas, FBO total timing limit plate so it's easy to ajust mecanical timing.