Firstly thanks for sharing. I'm not sure if you are asking me for a suggestion or just sharing but anyhow,
From what I see it was better before you add in the 2nd swirl bullet, maybe you can opt to take it out and see how things goes but then I cant offer any professional suggestion or opinions cuz I do
not have experience in modding exhaust.
Best if you post up this question the the exhaust thread, then other sifus might be able to
give better suggestions.