How well do ported 353 350 husky or 2152 jonsereds work?

[thumper]

im thinking of grinding my exhaust port 30 thous higher and lowering my intake 30 thous. maybe clean the sides of the transfers up. is this worth the trouble? or do i need more extentive work? i have a muffler mod and that seemed to help a little. 353 350h/2152j  i wish i could remember where my 500 partner went..lol