I'm a little confused on this, how to get rid of that annoying single pop sound when I shift. I'm running 15psi on my built b18c with 3" turbo back exhaust and my spark plugs are gapped at 28 thous.
Could it just be the gap on the spark plugs? or some other thing?

 

you sure it's not your general backfire pop sound?

 

You're tuned on Crome, tell me how I know that.