I don`t know, I have never done that myself. Some say that a mirror finish in the intake is not so good because the mixture is best atomised and blended if there`s small imperfections that cause turbulence that aids in the atomising of the fuel and air.

buggy engine modders often add epoxy in the intake corridor just below the carb to give a smooth turn for the mixture instead of it smashing straight down and loosing velocity. They try to make it a u-turn instead of aan almost 90 degree turn if you know what I mean. This mod is factory standard in higher end buggy engines.

I have also ground turbo cut in the crank of my ASP XLS 52, but didn`t tach it before and after, so I really don`t know if it had any positive effekt. I own several buggy engines and when I mod my aero and marine engines I try to copy some of what is factory standard in my Sirio buggy engines and then even add some more mods.