Extrude hone does not change the shape of a port, it only polishes what defects are there, sizes, curves, etc. I have flowed several on my flow bench after they were extrude honed, and they were all over the place in flow differences from port to port. The only way extrude hone is of benefit, in my opinion, is to gasket match the ports, shape them the way you want them, and do any plenum work you want before you ship it off to be extruded. The cost of shipping two ways, and the cost of each pass through the extruded makes it prohibitive for most folks. It works on EFI manifolds where you can't get to the long runners to port them, and since most EFI intakes are dry, the polished interior is a bonus. On a FE intake, you only get a polished interior, and not much improvement in actual airflow. Last time I checked the cost for an intake manifold was in the neighborhood of $700.00 for one pass, plus shipping. Joe-JDC