which Camshaft?

[67_camaroRS]

i have a 396 Big block motor with stock large oval port heads. Upgraded springs and rockers. stock rocker ratio. hardened pushrods etc. Stock crankshaft and new but stock style rods and pistons. It has a compcams #11-250-3 Cam in it. It has a choppy idle but has all the power at the high RPM range for a street car (67 Camaro). Duration Int/Ext: 284/296 -- Valve lift: 574/578 -- LSA 110. I'm looking for a cam that can deliver most its power in the lower to mid RPM range, and something that wont lose a lot vacuum. what can you guys recommend me? Thank you.

other info: TH400 tranny, 3.73 rear gears, 305mm rear tires,edelbrock performer air gap intake, 750 holley carb.