Really? I didn’t know that, thanks for letting me know, I’ll happily step away from the Dremel. I was told by an old timer to polish the ports for better flow… you just saved me several hours of work!
It will increase flow but the fuel slides down the wall, not flow into the cylinders as expected. It’s an old timer trick that showed cfm on the bench but not power on the engine as expected.
Better off doing a bowl porting and a race prepped valve job. This will effect flow in the lift range of the valve lift with the cam you have. (Or getting.)