ported and polished - whats it all about?

[Danno]

as above realy, if i aquire a head thats been ported and polished, whats been done to it???

[schakal]

inlet ports enlarged and casting marks removed to allow smoother
flow of air ,polishing is the final polishing of the surfaces . but from what i know its mainly needed on the zorst side to prevent carbon building .

dan or stan will probably give you a better answer :P

[sideways danny]

as above realy, if i aquire a head thats been ported and polished, whats been done to it???

how long is a piece of string?

Different people do different things. A well done basic head porting will blend the valve seats in for a much smoother transition on both inlet and exhaust, turn sharp corners into nicer radiuses, and give a better surface finish (different at different parts of the port)

You can go a lot further, spending time on detailing the combustion chamber, and balancing the CC, and increasing compression by skimming the head face.

Basically the aim of it all is improving flow and efficiancy, but there's different techniques for different requirements :)

[stan]

Anything from butchering it blindly, to modifying it properly is pretty much the jist of it!