For my 2 cents, if you'd like a slight lope at idle to make it sound good but not lose your driveability or vacuum, the Comp Cams 268 hydraulic is fantastic. It has just enough duration to sound like a 350hp cam and not kill your vacuum, and the lift isn't enough to worry about with stock springs. And it'll far outpull a factory 350hp cam because the lobe ramps are so advanced over the '60s stock hi-po cams. From experience I can tell you that a 350 with a 268 cam, headers and an Edelbrock Performer with a 600 Holley is a fun, peppy engine. Good luck!