Hey guys, I have a 2012 G37X Sedan 7AT with K&N drop-in filters, TopSpeed Pro catback and Berk HFCs. Before having the Berk HFCs installed, there was absolutely 0 rasp. After installing the Berk HFCs, there is a lot of rasp and kind of a hissing sound. See videos below:

https://streamable.com/0sf71
https://streamable.com/6eveg
https://streamable.com/auiq0

I'd say majority of the rasp is between the 2-3k RPM range. Is there some sort of exhaust leak? I've went to a few shops to have them inspect for exhaust leaks but they all said there was no exhaust leak. I believe they were only visual inspections, I don't think they used any of the methods that are out there to find them.
Is it the Berk HFCs causing the rasp? Is it maybe a bad gasket or near the o2 sensors?

Another thing I've noticed was that I was washing my car and I ended up putting quite a lot of soap and water into my exhaust (intentionally). When I went to go start my car and cruise around, it was significantly louder and deeper and there was 0 rasp, I loved the sound and wish my car always sounded like it. Maybe something to do with the water/soap affecting the packing of the muffler? See video below of some light revs.

http://streamable.com/8oujj

Why does having soap/water in the exhaust change it so dramatically? Does that mean there is something wrong with my mufflers? Is it harmful to put soap/water in the exhaust? I much prefer the way it sounds with soap/water in the exhaust, it's deep and there's no rasp whatsoever. If I wanted to obtain that, would I just have to get a muffler delete?

Sorry for the many questions but any feedback would be greatly appreciated.

Thanks.

 

 

I see, thanks for the info. If I were to delete my mufflers, would that cause my exhaust to be more raspy or less raspy? I really like how my car sounds when there is water inside the muffler and would like to achieve that affect. Do you know how I would go about doing that? The end goal here is to get rid of the rasp.