My old W5 Duster( many know it on here) ran well in the 9’s on 002/003 springs at 3350 pounds.
Nothing but CE 3 ways all around, no snubber, would hook anywhere, dial it blindfolded, super consistent wheelstanding crowd pleaser.
This on 28 by 10 DOT tires.
Frankly, at that power level, I heard more guys constantly fiddling with Cal Tracks than I ever heard with 002/003 leafs getting them to work.
A car either works or it doesn’t. If it doesn’t, you have to change something, but if it does work, “ upgrading” isn’t going to make it work better.