I got the 25mm just like the guys above. It plumbs in exactly like the one Stillen provides, same hoses, same clamps. I just had it in my hand the other day, but I didn't think to check if the recirc oriface opens before the vent to atmosphere does. I just assumed it did. It's just a plunger with two holes in the case. The recirc side has a nipple for the hose. Maybe one of these guys above can post a picture when theirs comes in. I bet the plunger moves and exposes the recirc side opening first.
I installed it at the same time I installed y'all's cog pulley idea. So I got a retune at the same time.
