Stock bottom end 360 magnum
Not completely “budget” but I did a 7.80 in the 1/8 with a rebuilt bottom end; hone, polish, new rings, bearings, oil pump and off the shelf 2.02 Eq heads, Oregon cam regrind, RPM Air Gap, 780 Holley. 727 with 3500 stall, 4.30 gears in a 3300 lb 65 Valiant. I later added a turbo to the same combo and went 6.90/105mph.