Time to tweak the carb again??

With all the little thing I'm messing with' I won't know what works by the time I get to the track next year.
Yesterday I pulled the distributor back out and pulled the heavy advance sprng off. Put the dist. back in and fired it up. Set the timing to 36 and set the idle mixture and speed.
The engine idles so much better now. Steady idle that doesn't wander high and low. I think I was fighting with the advance weights at idle speed.
SO any way.
I blip the throttle and it now has a wonderful hesitation #-o
Engine was runing around 150 deg so it shouldn't be because it was cold.
Prior to pulling the spring out it was running 36 total deg timing.
Now I don't understand why, if it's still set at 36 total timing, just all in at idle speed, why it now as this hesitation. It use to snap the rpm right up.
On a good note, on hot restat the engine just snaps to life, very short crank time.