The only company that I know of that uses velocity stacks on the inside of it's intake manifolds that I've seen, is JUN. And to tell you the truth, for the price of their manifold, you could certainly do many other things, that price for dollar would be substancially more affective.

Any way, their website last I checked, was something like Junauto.com

Good luck, let me know if you find anything aside from them.

Later,
Aj