964 heads

[r lane]

I have an engine down, 93 3.6 that is going to become a track motor. I am looking at the heads and remember reading about a liner, maybe ceramic that is in the exhaust port. At present there is a substantial lip where the liner transitions into the seat. I have read where some break the liner out of the port as that gives you a larger port, assuming you want that, but then the lip transition is worse. I would like to know how others have handled this. Also, the intake port has a nice consistent pebble texture to it. There is an on going debate on smooth vs ruff. Any info here would be appreciated. Thanks, Bob

[cgarr]

Where is the fuel going to enter the engine? If you have a fuel/air mixture (carbs) passing thru the port you don't want it polished, some texture is good like a course hone kind of texture. If you are injecting fuel right at the valve then you can polish the port.

[r lane]

MFI, so injector is where it would usually be, its snout pointing into the head's port. What is the theory behind how one chooses a port finish based on the fuel/air induction? Bob