I have a multi-part article running in Mopar Action right now on a 470 inch pump gas engine with Trick Flow heads. That engine is currently making 685 hp with a cast intake. I think I'll end up over 700 hp once I get a ported intake on the engine. I've tried three different roller cams so far in the engine and I might need to switch cams again to take advantage of the ported intake. So yeah, I think 700 hp is possible but I don't think the average Joe is going to hit it unless they copy someone's build. Most people don't try 3 cams, 4 intakes, and 4 carbs on the dyno like I have.