Hey guys. Anyone know if the stock headers with the Y-pipe on Springer Classics fit and create better torque than the true dual design?

I'm running Bub 7 True duals and they are ok. I lost a little zip on the low end but they look great and sound pretty good. I welded some lollipops inside the baffles themselves but they still lack the tq that I'm used to with the V&H big shots.

Thinking about trying to match up the Bub 7 slip-ons with the HD Springer headers. Any ideas?? Thanks