Since you uncorked the headers, whatever exhaust you get will be quite loud especially if it replaces the 2nd resonator closest to the muffler.
I wouldnt expect too much or if any gains in power, but it sure is going to sound great.
"I call suffering my brother. I love him like my mother. We look out for each other, we'd die for one another.
I fight, I brawl, I feind for this. I scrape, I crawl, I bleed for this.."