340 help/advice

k so i left some stuff out lol...727 auto trans, gear still stock but want to go with 8 3/4 373ish ratio somewhere in that range, headers, small bolt pattern wheels gonna up the rears? would like to use a stall 2500 rpm or so depends on the cam, lookin to build a driver but want some decent power, guess i used the wrong word as "thumper" lookin for a strong runner with a nice sound, crane cam in it now #'s 238/320, should i go roller? plan was tappet