Ok, is this effective?
What flow gains can I expect?
Also, could my porter damage the velocity distribution of these heads?
How much should I look at spending?
Who can port them?

 

Here's what you can do. Sell me your heads to me for $900, and get the 220's. That would be too easy for me though. You could easily get a lot of $$$ for your heads. If I were you I'd really look at the 220's. Get those do some extra porting, get a ridiculously huge cam and have a 11 flat 406.

 

If you want them ported let me know. My friend owns coupe performance. He is one of the best known secrets to the head porting world!!! His car runs 9.20's in the 1/4 and he drives it to the track...!. I can get them done for you for 500.00. If you do port them I would get a bigger cam. The higher lift the more you will use the head. My heads flowed 259 at .550 lift. and at 600 lift the flowed 267, but my cam will not allow me to use the extra power. My other set of heads afr 190s 68 cc flowed 281 when fully ported at .570 lift. MY friend does awesome work! let me know you can call em at 478-457-7503 if you have any questions. He just did a set of ls1's that flowed 303cfm!!!!

Drew

 

Your flow #s on your first set of heads NOS GTA are what my 190 AFRS flowed out of the box, I had merely a bowl job and better valve job done and the 190s flowed 272 cfm @ 550 lift int. and 215 cfm @550 lift on exh. Just think what a good porter could do!!! (like your freind)
In my opinion I would get your 190s ported expertly and youll be fine.
Perry