Has anyone tried this on a Prairie 650? How is the performance increase if any, how loud, and how did it effect jetting?

 

Most people I see either go with the Utility Series or the Penland Race series so I don't know if you'll get too many people to comment on personal experience with the Eco System. I do know that the Eco System does not offer the same power gains as the Race Series, but it is a lot quieter (same db as stock at idle and 94db at mid throttle). The race series is 106db and 97db with the quiet core. I'd call HMF and ask them for some numbers 1-866-HMF-PIPE. Here is the race series.