I have the 17733 on the Dart and 17748 that I got from TTi when I bought the system for my Bee .I just realized the 747 is 2.25 tail , 748 is 2.5.

I wonder if Dynomax changed the design because the charts says 410cm flow but the box , I still have them with 3" borola xr1's in them , says 376cfm ?

running up my post count some more .