Of course, I can no longer find the post that I recall explained it, only references to it. I also failed to mention that previously I had removed the secondary butterflies. I talked to my tuner yesterday. The different stacks didn't illicit a reaction although he did say that he could have fixed my issue on a stock bike. His only concern was achieving a good result without the secondary butterflies. So when I meet up with him next week, I'll bring both stacks and the secondary butterflies just in case. For the time being, I'm enjoying the bikes behavior at lower RPMs. Can't say if it's making the same power up as I feel the added induction noise would be influence my opinion. The dyno results will be interesting.