I'm giving this a try myself for the 1st time on heads. check out this thread.http://www.sccoa.com/forums/showthread.php?t=132192. I should be putting up pics by this weekend. I've also been watching headbytes porting on youtube. The guy gives up close longer videos and explains as he goes. It's kind of black magic from what I'm seeing...not easy at all and several hrs or work may or may not pay off (for a rookie). Some mods show up on a flow bench but not the dyno or track or vice versa. I'm just going to follow the advice in the above thread...grind, polish and see what happens.