Originally Posted by kellygnsd
"race prepped" means whatever the shop building the heads wants it to mean. Don't become preoccupied by key words and tricky phrases. Find out what you want done to your heads and commission a quality shop to get it done. After that you can call them whatever you want.
I'll ask the question differently : what could be done to the head to improve performance and what are the upsides / downsides to it ? I know a little bit about components as I said above but I don't know much about machining and the effects it'll have. It may be a newbe question but I cannot find any search word on google / nasioc that'll give me more than "race prepped" heads the way you stated it.
If you have any link to help me, it would be much appreciated.