Joe Byrd on this board (battleax) had this idea of using a velocity stack of sorts to change the power characteristics of H1's and H2's.
viewtopic.php?f=2&t=606I am in the middle of experimenting with another version that I am anxious for someone else to try as it is so cheap and easy.
I originally used PVC schedule 40 elbows and thought they softened the hit too much probably due to the smaller ID; have since bought some schedule 80 elbows and will try them next.
Now for something simple:
My 72 H2 with stock carbs and Denco's now has Fernco rubber plumbing connectors for 1 1/4" pipe and are 3 1/4" long.
The hit is still softened but much like Joe's post, there does seem to be more bottom and a smoother transition. Am wondering of the power is still there but spread around, and, that the loss of "coming on the pipe" confuses the butt dyno.
Since these couplers are only a few bucks a piece I thought someone else might to give it a go.
I screwed up my old pods while playing with PVC and Rube Goldberg adapters and just zip tied them on the end of the Ferncos. For a quick try, one could run it with no filters (although I can't bring myself to with all the grit on the roads here).
Be prepared, this is ugly: