Originally Posted by LilWhtTaco
well i dunno about the 1gr but with the 2rz intake mani its been said that the design is pretty damn spot on and while, yes there is room to port and polish, the money and time to do it can be better justfied elsewhere.
Just took out the top intake plenum during a recent install, and looking into the manifold, I would say the same for the 1GR. But, if you have the time and or money it could be done. It would probably be a fun project.
What would be awesome is if you got before and after Dyno runs. But then again that will cost more