you can get more power with a cam
but if you want the same rpm range then you need to keep the effective duration near stock
doing manifold and small 4bbl-
I recommend an AVS gives you more power without having to change converter and gears which is what you have to do if you start closing the intake valve too late
Air Valve Secondary will not open more than you engine can use
Other and IMHO better choice with maybe a little more learning curve is a 318 Mopar Thermoquad
Back to cam
stock cams tend to be lazy and close the intake and exhaust late when looking at when they actually close
the 360 cam is worse and the 340 HP cam is way wrong- lots of threads here from those that have tried it It wants high compression and higher revs even in a 340 or 360
The summit cams are old cam dynamics grinds now ground by Crane (and several others)
post up your compression and the rest of your details in ONE POST and let AJ/formS take a look at them
custom cam and solid lifters solves lots of problems
IMHO best off the shelf cam would be the smallest Lunati Voodoo
no other suggestions till I see compression gears body etc
I take it no headers- that makes a difference
was it you that was thinking of changingheads?