I see sometimes in people's sigs 'mild port work' and such. I'm curious on reasons why some don't just do full blown porting on everything. This is probably a naive question but I would just assume the more port and bowl work type stuff you can do the better. I can understand two reasons: if you're having someone else work your heads it costs a lot; or if you're DIY you probably don't want to try anything too 'risky' and damage your heads. Is there something I'm missing, maybe circumstances where you don't want things ported and worked over or anything like that? Thanks.

"mild" bowl work can help flow across the board..full blown port work can/will hurt low lift flow while increasing high lift flow. Also port work done by someone who is not experienced, will hurt flow. I have a set of Dart 230's. Out of the box, they looked terrible. The seats stuck out .200. So a bowl clean up was mandatory, but my head guy said that there is a ton more potential with further porting...for a lot of cash..lol

ive been told by several engine builders that the best bang for the buck is in the first 3-400 dollars worth work. Like the post above said anything over that can actually hurt the lower end. But the guys doing the "full blown" work arent running thier cars down low much.