Free cam build...

Mostly because of the very slow lifter rates off the seat. A chevy cam (and a slow rate one at that) that doesn't take advantage of the mopar lifter diameter. And, it's not really much of a street grind, unless you can stand to live with 4.56 gears and build it with 12:1 or better. But a 408 or 416 will tame it down a little more than if it were in a 340 or 360 and will drop the upper rpm range a few hundred rpm. You'll need to plan on oil and cooling system improvements. It would also be a good idea to look at a B3 racing engines rocker correction setup with the projected rpm range. And it's going to take a lot of cylinder head to flow over 400 inches at 7 large. TFS, Victor, Indy or W2, maybe Brodix B1-BA. A build around this much cam can get "spendy" pretty quickly. But if you've got the cubic dollars and really want to make it happen, it would make a plenty hairy street engine. I like this stuff based on "pick a cam from near the bottom of the page, that's where they hide the good stuff" mentality. Practical, it aint, but it sure can be a lot of fun!