About Exhaust Sound

Normally, I do not enjoy it, but I had a flat pipe last summer with a whim. I had the muffler put back in 2-3 days due to excessive sound.
Thanks to cousins and friends, they entered my blood again. A little voice a little voice. I went to the same exhauster and told him what I wanted. I asked if we could get a little sound by drilling the muffler. He said, we'll handle it, we'll do it. When he entered the channel, he proceeded to the engine part of the vehicle and made a hole in the flat part. Not to the muffler. When I run it, the sound was no different from the straight pipe. Filled with the source again. Something pierced again, something. We struggled a bit until we found the sound I was looking for and we took care of it. I like the sound. Even those who do not know the sound. It just sounds like there is a leak.

The problem is, I wonder if there is an event of throwing out unburned gasoline, as in the straight Pipe. So I'm concerned about fuel consumption. I tried to explain quite clearly. I hope I could explain it fully. I am waiting for your ideas and opinions.