why more decel noise in 2nd gear than 3rd or 4th?
 

Working to tame my decel cackling...
I notice when I lift off gas and coast down from 2nd I get a lot of cackling and popping.
When I do the same in 3rd and 4th I get some, but much less.

Why is this the case? Is it purely from drawing a stronger vacuum in 2nd? Why would this make more popping?

Trying to figure it out so I can try to tune around it. I do have EFi and currently my fueling cell values are set to give me 14.5 AFR at low vacuum (below 32 kPa).