It's definitely possible to increase the gurgle/pop on decel. Either by leaning it out some or richen it up. I have a 2002 cbr 954 that had some terrible popping on decel. It has a valve that feeds fresh air into the exhaust which causes unburnt fuel to burn. I placed a marble, yes a marble, in the vacuum hose that feeds this valve and it completely eliminated the popping.

 

Wow thats crazy. I would be real hesitant about tuning the car for fuel mixture as im not too familiar in that area. I am hoping however that the BBK long tubes, BBK catted x pipe and Pypes Pype bomb super system will give me the popping on decel. I know it should be a good setup (at least i think)