Loud noise when letting off gas?
 

To start, the only engine or exhaust mod I have done is a muffler delete going into a single exit. When I'm driving over 40mph and let off the gas completely, the car makes a loud and deep sound, almost as if the engine revved higher. Best way to describe it is as a deep growl or maybe even deep pop.
Anyone have any similar issues?

The sound comes from beneath the car, I would say in the exhaust but I didn't drive log enough to feel specifically where.

You mean...like this (0:35)?

https://youtu.be/-_POifjv2Xg?t=35


Normal.

No, it isn't that high pitched/backfire like. It's innedistely after I let off and it's a sort of roaring or like deep pop.

=/

Please make a audio/video recording and post it.

Muffler delete will do that. The only thing surprising here is that you are surprised.

heck i installed a tomei 60R catless mid pipe today and i sorta get that pop sound, on a fully stock exhaust willing to bet its the muffler delete