Best Cylinder Head Porting Shop/Vendor- Your Experiences w/Results

I think in your case what you should do is call the porter of your choice that is close to you. Talk to them about your engine. Go to their shop, look around.

Ask what they can do to reach your goal and how much it will cost.

If you want to make power there is nothing beter than having a friend or a shop that you trust.

Like others have said, port flow is just a part of the equation.