Possible issue w Detonation. Cracked several pistons in land between compression rings. After new pistons installed want to make sure timing is right. On multiple Rides I’ve had E-Dist’s w no vac. Advance. For initial timing I’ve always timed the same as stock Dist’s w vac adv. using factory recommended for the engine. I’ve always thought til this issue that was good because vacuum vertically is gone as E-Dist. reaches 2500-3000 rpm preset advance is fully engaged. Thoughts?