Even if they do flow well for the GSR intake ports, the plenum is much too small and the runners don't flow as well as a Skunk2 (Type R replica) would for higher rpms. If you are itching for something more, get your intake ports done and port the Skunk2 to it.

I dug up this manifold tech article for you: http://www.team-integra.net/sections...?ArticleID=466