polishing?

[Kamofly]

when you guys port/polish, do you also polish combustion chamber? If so, what does this do to your compression ratio?
( stock bore & pistons w/ "fatty" pipe)
thanks 4 th input!

 

[Pantaz]

There are differing opinions on this subject, but polishing the combustion chamber should not make a meaningful change to the compression ration. You will be removing only a tiny amount of metal.

 

[David Trustrum]

Indeed the polishing should be done on the outside of the head.

You won’t find a decent engine tuner polishing ports or C.chamber of their own bikes, but some will send customers parts back like that ‘cause it looks trick.