stockish 340 maybe a 6 pack good or bad ideal??

so i have a 340 in the car now i can tell its been gone thru but dont know any thing about it.
i would say no more then 10 to mild cam stock x heads
hp manifolds elc ing

im wondering if i throw a 6 pack on here what it will do kill the car or make it fly. not sure even if i down jet it if the flow is right some motors just dont run with some set ups

so whats your input


well if you really want to know what you got i would pull the heads and cc them, along with cyl sizes, figure out compression, then "degree" cam to find lift and duration for general cam specs... thats the extreme tho...