Running a mostly stock 400 in my barracuda. Only modifications are 600cfm carter carb, K&N x-stream filter, 1/2" carb spacer, MSD digital 6AL, Mopar adjustable distributor, crappy headers made for a b-body, and a cheap summit camshaft (very mild grind). Transmission is the stock 727 that came with it, very low stall on the torque converter. 3.23 sure-grip out back with 14" wheels and tires.
Ran a best of 14.60 at 98mph this summer on street tires shifting at 5,000rpm. Much better than I expected for a pretty much stock 400