John, a friend of mine has a 327 with no blower or nothing sitting on a stand in his shop. He said before he pulled it out he had a bit over 400 HP. I can ask him what he has done to it and his oppinions on what kind of cam to run in it, etc since he is really into 327's and 400 small blocks. I think you can get around 350 HP no problem with a bit of money of course and have a nice streetable car though. Won't be the best on gas but then again wont be a total guzzler. I can't say too much on this subject though since I am still learning as well but basically techinspectors comments are true. Give me about a week or so for the guy to come back home and I will talk to him about his 327 and what he thinks on the cams, heads, etc.
Another option while you are waiting is call or Email Summit racing and tell them EXACTLY what you have in the motor now, what's done to it, what tranny you will run and the car it's going in and tell them you want to push around 350-400 HP and what they think can help you get there for the heads, cam, and everything else you need to complete it. Now if you want to run a certain brand like Edelbrock then contact them, tell them the same thing and then contact Summit and ask them about the electrical system and which one to get with the setup after ordering the Edelbrock. See what I am getting at?
Good luck on the build, 327's are awsome motor's and something a little bit different than the 350 like you see a lot.