Had 002/003 leafs on my old car. Weighed 3350.
Used the simple Comp eng 3 ways on the back. Car went 1.34 with them, and from outing to outing was very consistent.
I doubt another shock would have shown any gain. It dead hooked everywhere.

69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight
418 BPE factory replacement headed stroker, 565 lift solid cam
Best so far, low 10.30’s 1/4
1.41 best 60 foot
6.56 at 104.17