351W Edelbrock RPM head porting?
Why have I heard that it's not worth it to have Edelbrock RPM heads ported? I have the #60259 heads. I have an old tappet 351W block with dished .060" pistons. A shop here in town milled the heads at their "max" (?) to try and give me 9.5CR because the owner of the shop says my motor had 8.5CR pistons. I have the Comp XE274H cam with RPM air-gap intake and Holley 750Vac carb. I also have a modified manual C4, 11" - 2500 converter and a 4.56 rear. Because of my dished pistons - which that shop also flycut so the 2.02" valve reliefs "worked" - and since the current heads are already milled - rather than spend a couple of thousand $ to get better heads and then get them milled - I was hoping it would be feasible to have these Edelbrock RPM heads seriously ported so that they flow better than 251CFM at .500" lift if I'm quoting Edelbrock's flow chart correctly. I am looking for more top-end HP while keeping it under 6000RPM.