i started at 0 degrees btdc, 900rs vac gauge hooked up, vac advance di connected the reading on the vac gauge is 10. i kept turning the distributor little by little and resetting the idle to 900rs until i reached the highest vac reading 13 inches 22 degrees btdc 900 rs . it got hard to read between 18 and 22 btdc looked like double lines on the ballancer. i droped the dist back until the vac dropped one inch the timing is 20btdc 900rs when i put it in gear it dropped to 650rs and barely idled i turned the dist to 18 btdc moved the idle to wear it would idle in gear 1100rs 13inches vac reconnected the vac advance reset the idle readjusted the mixtures approx. 4 turns out the motor did get more torq after adjusting the valves back half turn last nite and i did find something strange. i have a proform shift lite in he car it has adjustable dial to set rpm shift points i had the power wire hooked to the dash lights cause i always run with parking lights on .while driving the light would flicker i thought it was the head lite switch when i would turn the dimmer it would stop today i decided to hook it to the fuse box , going home i hit the gas to make sure the light was going to work it worked perfect about 15 minuts in my ride the lite started flickering again thats when i realized it aint the switch then i realized about 18 to 22rs were the car had the so called vibration is when the light would flicker i kept hitting the gas playing with it all the way home it kept doing it and would feel that vibration like flutter thing 18 to 22rs. could it be that the distributor is loosing spark at that rpm? hmmm you can kick it in the ass and shell launch perfect burn rubber never pop or mis i shift at 5300 with no problem at all just wont idle has low vacuuum and a srange feeling at 18 22 rs i hope this helps