homemade velocity stacks

tonight i tried my first attempt to build my own velocity stacks in a lathe.
not to bad for the first try, need to work more in the visual aspect of the stack, but lets see
how it perform in a prb test intake manifold.....

there is a neat gain of 30CFM,before and after the velocity stack.  the rsp intake manifold comes with
some velocity stacks, but they lack of any bellmouth...

the idea behind this is to build some velocity stack for a fn2 intake manifold, which i tried earlier but failed. jenvey velocity stacks are too big  to weld them inside an oem intake plenum, they have too much bell for an oem manifold.  secod goal is to be able to tune the length  of the runner to play with harmonic resonance.