Anyone know of a head and cam package that will put at least 400hp or more at the wheels? Please include price if you know them.

 

Lloyd Elliot's porting service, they specialize on LT1 heads. Cam & head packages 370 to 430 RWHP using a 350 C.I. LT1. Prices: $1200 to $2050 for head & cam package, $750 to $1700 heads only. You have to provide good head cores.
http://www.eportworks.com/lt1.html