I have the DC mechanical carbs on a Hughes deep-ported factory-style aluminum sixpack intake on my 493" stroker motor. The combo can make some impressive top end power when set-up right.

Since the motor was dynoed, I've upgraded the rocker arms to 1.6 to 1 ratio T&D's with Manton pushrods. It gave me about .050" more lift and a touch more power everywhere especially on the top end. The motor still wants more cam, but I don't want to give up the power on the bottom end. It street driven 99% of the time, and already rev's like a small block.

Here are my dyno sheets contrasting the sixpack's performance with a big 4 barrel carb and intake. These numbers are with .050" less lift than it has now, but it is still a pretty healthy street engine.

http://www.hughesengines.com/TechArticles/3dynotest684hp500cid6pack4bbljcross012007.php