Summit 3" Duster Install
Weather probably picked you up some as well.
Since the 60' didn't change much, the exhaust/open isn't creating much difference down low. Next time, run it corked up, then open to see if it makes a difference.
I've had and worked on cars that made .15-.25 pick ups changing the fuel line diameter.
The two items that picked it up were the line change and jetting jump. I'd love to see what the car would have run with the 5/16 line and bigger jets? I bet it wouldn't have gone 109+. Your test with the bucket proves the point!