I ran consistent 11.40-11.44 with the following, in a '70 Duster @ about 3200 lbs with me and 10 gals gas in it:
358" 340, ported X heads, 750DP Holley, single-plane intake, MSD, Crane MFT .580/.600 lift, 12.5:1 CR, Stahl 1 7/8 headers.
Holley blue, Moroso electric water pump, pan evac, 8-point cage. 7.10s on 15x4s in front.
Jack Arnew's modified upper control arms (car always went dead straight & carry ft wheels at launch).
4400-stall TA converter, RMVB mostly stock 904, Dana 60 5.38, 13x31s on 15x12 wheels (mini-tubs, springs moved to rails).
The fewer pounds you have to move, the better for literally everything. That said, it always liked more ballast in the trunk.
It was never a street car, so everything that wasn't needed was gone except 1 seat and a finished interior.