Looking for more pep off the line

Hey all,
I've got a 73 Duster with a 360 LA and 727 that I rebuilt myself, and I'm looking for suggestions to make more power down low. The engine is bored over 0.040, has KB 107 pistons, 9.6:1 compression ratio, stock crank and rods, Summit K6901 camshaft 218/228 0.441 lift, stock J heads, stock cast iron intake, Holley 600 cfm vacuum secondaries, TCI 141500 converter, 3.23 rear gears, timing set at 12-15 degrees BTC. My build is meant to be a street machine on a budget, it runs well but it feels a little lacking off the line. Any suggestions for making better power would be much appreciated.